=Paper= {{Paper |id=Vol-3777/paper8 |storemode=property |title=The COVID-19 Pandemic Dynamics and Incomes |pdfUrl=https://ceur-ws.org/Vol-3777/paper8.pdf |volume=Vol-3777 |authors=Igor Nesteruk,Oleksii Rodionov |dblpUrl=https://dblp.org/rec/conf/profitai/NesterukR24 }} ==The COVID-19 Pandemic Dynamics and Incomes== https://ceur-ws.org/Vol-3777/paper8.pdf
                                The COVID-19 Pandemic Dynamics and Incomes
                                Igor Nesteruk1,2, Oleksii Rodionov3
                                1
                                  Institute of Hydromechanics, National Academy of Sciences of Ukraine, Kyiv, Ukraine
                                2
                                  SBIDER (Systems Biology & Infectious Disease Epidemiology Research) Centre at University of Warwick, UK
                                3
                                  Private consulting office, Kyiv, Ukraine

                                                               Abstract
                                                               Objectives. Large differences in the number of registered SARS-CoV-2 cases per capita in different
                                                               countries encourage research into the causes of this phenomenon. In particular, the accumulated numbers
                                                               of cases per million (CC) demonstrated strong linear correlations with the gross domestic product per
                                                               capita (GDP) and the median age of populations. In this paper the possible correlations between GDP and
                                                               numbers of cases CC and deaths (DC) per million, case fatality risks CFR=DC/CC, vaccinations and
                                                               testing levels will be investigated. As well non-linear correlations of CC, DC and CFR values versus
                                                               vaccinations and testing levels will be considered.
                                                               Methods. A non-linear correlation and John Hopkins University (JHU) datasets for African and European
                                                               countries corresponding to August 1, 2022 were used.
                                                               Results. The numbers of CC, DC and CFR increase for richer countries, the same trends were revealed
                                                               for DC and CFR values in Africa, but opposite ones in Europe. As expected, the testing and vaccination
                                                               levels increase with the growth of GDP. Higher levels of testing probably allowed revealing more cases
                                                               and COVID-19 related deaths in rich countries. CC values showed a very strong increasing trend with the
                                                               increase of numbers of tests per capita (TC). Unexpectedly, the same increasing trend was revealed for CC
                                                               and DC values versus percentage of fully vaccinated people (VC). Nevertheless, the decrease of CFR with
                                                               the increase of VC demonstrates a positive effect of vaccinations.
                                                               Conclusions. In some countries, the number of undetected COVID-19 cases may be tens or even
                                                               hundreds of times higher than the number of registered ones due to the differences in testing levels and
                                                               age structure. This fact increases the probability of the appearance of new dangerous SARS-CoV-2 strains
                                                               and has to be taken into account in further investigations of impact of different factors on the pandemic
                                                               dynamics.

                                                               Keywords
                                                               COVID-19 pandemic, epidemic dynamics in Africa, epidemic dynamics in Europe, gross domestic
                                                               product per capita, non-linear correlation, statistical methods.1


                                Introduction
                                The general characteristics of the COVID-19 pandemic dynamics require further research despite
                                the vast number of available publications, including studies comparing the COVID-19 pandemic
                                dynamics in different regions and the impact of various factors [1-18]. In particular, a strong linear
                                correlation was revealed in [18] between the gross domestic product per capita (GDP) [19] and the
                                numbers of cases per million (CC) registered in African countries as of February 1, 2022, [20]. In
                                this study, a non-linear correlation between incomes and values of CC, accumulated numbers of
                                deaths per million (DC) and the case fatality risk (CFR=DC/CC) will be investigated with the use of
                                datasets for African and European countries corresponding to August 1, 2022, [20]. We will also
                                discuss the possible influence of the accumulated numbers of tests per capita (TC) and the
                                percentage of fully vaccinated people (VC) on the CC, DC and CFR values.




                                ProfIT AI 2024: 4th International Workshop of IT-professionals on Artificial Intelligence (ProfIT AI 2024), September 25–27,
                                2024, Cambridge, MA, USA
                                  inesteruk@yahoo.com (I. Nesteruk); aleksei.rdnv@gmail.com (O. Rodionov)
                                   0000-0001-7250-2729 (I. Nesteruk); 0000-0002-4466-2183 (O. Rodionov)
                                                        © 2024 Copyright for this paper by its authors.
                                                        Use permitted under Creative Commons License Attribution 4.0 International (CC BY 4.0).
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                                                        CEUR Workshop Proceedings (CEUR-WS.org)


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                  ceur-ws.org
Workshop      ISSN 1613-0073
Proceedings
Data, the non-linear regression and Fisher test
We will use the data sets regarding the gross domestic product per capita (GDP) based on
purchasing power parity (PPP) available in [19] and some COVID-19 characteristics reported by
John Hopkins University (JHU) as of August 1, 2022, [20]. The figures corresponding to the
versions of files available on September 4, 2022 are presented in supplementary Tables S1 and S2
and shown in the Figure for African (black markers) and European countries (blue markers).
   The following non-linear correlation will be applied:

                                 y = a + b( x + с)g ; a ³ 0 , b>0, x>-c                             (1)

to find links between GDP, TC, and VC (variable x) and CC, DC, DC/CC, TC, and VC (variable y).
At γ =1 relationship (1) reduces to the linear one. It can be also reduced to the linear correlation by
using new random variables z and w≡log(x+c), [11, 14]:

                                z≡log(y-a)=log(b)+γlog(x+c)                                          (2)

    The constant parameters γ, log(b) and corresponding best fitting lines can be found with the use
of standard linear regression formulas [21] for different values of constant parameters a and c.
Their optimal values correspond to the maximum of the correlation coefficient magnitude |r| or the
ratio of the Fisher functions F/Fc(k1,k2), (k1=1, k2=n-2, n is the number of observations, i.e., the
number of countries in datasets), [ 6, 11, 14]. The corresponding experimental values F can be
calculated with the use of formula (S1), [21], the critical values Fc(k1,k2) of the Fisher function at a
desired significance or confidence level can be found in [22]. If F/Fc(k1,k2)<1, the hypothesis about
the relationship (1) is not supported by the results of observations. The highest values of F/Fc(k1,k2)
correspond to the most reliable hypotheses.

Results
The optimal values of parameters for different non-linear correlations (1) are listed in Table 1.
Corresponding best fitting lines are shown in the Figure by the black color for African datasets,
blue - for Europe and red - for complete datasets (Africa + Europe). Rows 1-3 of Table 1 and solid
lines in Figure illustrate that the accumulated numbers of cases per million CC always increase
with the increase of the incomes. Nevertheless, the number of deaths DC and case fatality risk CFR
decrease in richer European countries (see rows 5, 8 and blue dashed and dotted lines; the
correlation DC versus GDP is supported at confidence level 0.025; Fc (1, 40) =5.47). What is
surprising is the increase in DC and CFR values with increasing income in Africa and for the full
data sets (see rows 4, 6, 7, 9 and corresponding dashed and dotted lines; the correlation CFR versus
GDP for complete dataset is supported at confidence level 0.005; Fc(1,94) =8.33).
     As expected, the vaccination and testing levels (VC and TC) always increase with rising
incomes (see rows 10-15 and corresponding lines). Rows 16 and 18 represent the correlation of CC
values versus TC and VC, respectively. The strongest link between the number of cases and the
testing level (r=0.9496, and the highest F/Fc(k1,k2) ratio, see row 16) and the strong link between
TC and GDP values (see row 12) allows us to conclude that high CC values in rich countries are
probably connected with the higher testing level. Numbers of cases and deaths per capita for
complete dataset (Africa + Europe) increase with the increase of percentage of vaccinated people
VC (see rows 18 and 20). Opposite trend was revealed only for CFR values (row 22). Thus, the
positive effect of vaccinations is visible only in decreasing the probability to die for persons tested
positive. To eliminate the influence of the testing level the same correlations were investigated for
15 European countries with TC>3. Corresponding CC, DC and CFR values demonstrate decreasing
trend with the increase of VC, but it was not supported even at the significance level 0.05 (Fc
(1,13)= 4.67; see rows 19, 21 and 23).

Table 1.
Optimal values of parameters in eq. (1), correlation coefficients and the results of Fisher
test applications for Africa, Europe and complete datasets (Africa + Europe).

                                                                                                       Experi-    Critical
                       Num-       Corre-        Optimal       Optimal       Optimal       Optimal      mental    value of
          Charac-        ber      lation       values of     values of     values of     values of    value of    Fisher
          teristics       of    coefficient    parameter     parameter     parameter     parameter       the     function
 No.    y in eq.(1),   obser-                                                                          Fisher    Fc(1,n-2)
           dataset       va-         r              a            b             c             g        function    for the    F/Fc
                        tions                                                                           F, eq.    confi-
                                               in eq. (1)    in eq. (1)    in eq. (1)    in eq. (1)     (S1),      dence
                         n                                                                              m=2        level
                                                                                                                  0.001,
                                                                                                                    [22]

                       Relationships versus gross domestic product per capita (GDP), variable x in eq. (1)

 1      CC, Africa       54       0.7353      0               0.1188           0          1.3038        61.22     12.35       5.0

  2    CC, Europe        42       0.7206          86929.3     126.16       -11649.8       0.71678       43.20     12.87       3.4

  3       CC, all        96       0.9110            0         0.0239           0          1.5141       458.63     11.66      39.3

  4     DC, Africa       54       0.9013          3.02799     0.0277       -855.999       1.0143       224.98     12.35      18.2

  5    DC, Europe        42       -0.3516           0       1.0965e+5          0         -0.36425       5.64      12.87      0.44

  6       DC, all        96       0.9122          3.02799     0.0257       -855.999       1.0466       465.82     11.66      40.0

  7    CFR, Africa       54       0.7313       8.3881e-4     3.8836e-5      -855.99       0.72518       59.76     12.35       4.8

  8    CFR, Europe       42       -0.6800           0         355.45           0          -1.011        34.41     12.87       2.7

  9      CFR, all        96       0.3145       8.3881e-4     8.1292e-4      -855.99       0.25827       10.32     11.66      0.89

 10     TC, Africa       49       0.6956            0        1.0880e-5         0          1.06281       44.05     12.56       3.5

 11    TC, Europe        39       0.6994           0.442     8.3847e-6      12985.5       1.19322       35.44     13.00       2.7

 12       TC, all        88       0.9023            0        1.0167e-6         0          1.36422      376.67     11.74      32.1

 13     VC, Africa       53       0.8503          0.1299      0.0857        855.998       0.67441      133.07     12.39      10.7

 14    VC, Europe        41       0.7890            0         1.4678         7184         0.35864       64.31     12.91       5.0

 15       VC, all        94       0.8653          0.1299      0.1440        855.998       0.58839      274.08     11.68      23.5

                       Relationships versus accumulated tests per capita values (TC), variable x in eq. (1)

 16       CC, all        89       0.9496            0        9.689e+4          0          1.02755      797.62     11.73      68.0

 17     CC, TC>3         16       0.4006            0       3.3714e+5          0          0.15396       2.68      17.27      0.16

                       Relationships versus percentage of fully vaccinated people (VC), variable x in eq. (1)

 18       CC, all        96       0.8348          3609.84     4.4063           0          2.50244      216.20     11.66      18.5

 19     CC, TC>3         15       -0.3818         214294    6.3205e24          0         -10.6211       2.22      17.93      0.12

 20       DC, all        96       0.8185          3.0275      0.9319        0.1171        1.72795      190.85     11.66      16.4

 21     DC, TC>3         15       -0.4486           0         5.4599e6         0         -1.82403       3.28      17.93      0.18

 22      CFR, all        96       -0.4397      0.003983       0.0471           0        -0.60571        22.54     11.66       1.9

 23    CFR, TC>3        15        -0.2766           0         0.0439         36.15      -0.61497        1.08      17.93      0.06
Figure 1: Characteristics of the COVID-19 pandemic in Africa (black) and Europe (blue) versus
gross domestic product based on purchasing power parity GDP (PPP) per capita in international US
dollars

    The characteristics accumulated as of August 1, 2022 are: numbers of cases per million (CC,
“circles”), numbers of deaths per million (DC, “crosses”), percentage of fully vaccinated people (VC,
“dots”), numbers of test per capita (TC, “squares”). The case fatality risk was calculated with the
use of formula CFR=DC/CC and shown by “triangles. Lines represent the best fitting relationships
(1) with the optimal values of parameters listed Table 1: the black color corresponds to African
countries, the blue one – to European, the red one – to complete datasets (Africa + Europe).

Discussion

   The large difference between the number of registered and real COVID-19 cases [23-33] has to
be taken into account to investigate the effects of different factors on the pandemic dynamics. In
particular, different healthcare infrastructures, public health policies, and social behaviors could
significantly change the pandemic dynamics and the analysis of these factors needs further
investigations. Here we will focus on some specific influence of the testing rate. In particular, the
TC values could approach some critical level, which allows revealing almost all COVID-19 cases.
To check this hypothesis, let us consider the countries with TC>3. Their relatively large number -
16 (all countries are located in Europe) - allows drawing some statistical conclusions (see row 17).
First, there is no correlation between CC and TC values even for significance level 0.1 (Fc (1, 14)
=3.14). It means that 3 or more tests per person were enough to reveal the majority of cases before
August 1, 2022. Its average value CCa is approximately 460,834 and can be used to calculate the
visibility coefficient

                                                ССa
                                           b=                                                       (3)
                                                СС
as the ratio of real to registered number of cases.
    There are some theoretical and experimental estimations of the visibility coefficient for different
periods of COVID-19 pandemic [10, 23-25]. For example, a total testing in Slovakia (89.5% of
population was tested on October 31- November 7, 2020) revealed a number of previously
undetected cases, equal to about 1.63% of the population [23, 24]. Taking into account that the
number of detected cases in Slovakia was approximately 1% of population [20], we can estimate
β≈2.63 for that period in Slovakia. As of August 1, 2022 the corresponding value CC=473,844 for
Slovakia (see Table S2) is slightly larger than CCa showing the good detection level in this country
with TC=9.41.
    A random testing in two kindergartens and two schools in the Ukrainian city of Chmelnytskii
[25] revealed the value 3.9 in December 2020. Theoretical estimations based on the generalized SIR
model [6, 10] yielded values from 3.7 to 20.4 for Ukraine and 5.4 for Qatar in different periods of
the COVID-19 pandemic. As of August 1, 2022 formula (3) yields the β values 3.8 for Ukraine and
3.0 for Qatar (CC=152,375.8, [20]). Corresponding visibility coefficients are: 4.4 in Japan; 1.7 in US
and 14.7 in India.
    The value CCa = 460,834 and formula (3) is probably not applicable for China and other Zero-
COVID countries [34], where the total control and maximum suppression of the pandemic were
applied. For example, mainland China has achieved the testing level TC=6.46 already on April 11,
2022, [20]. The value CC=636 registered on August 1, 2022 is much lower than the CCa figure.
Nevertheless, CC values in Australia, New Zealand and South Korea (where the zero tolerance
policy was not as severe as in China) CC values vary from 317,619 to 384,572 (see [20]). The testing
levels in Hong Kong (TC= 6.59 as of May 24, 2022, [20]) and in mainland China are very close. The
huge difference in the registered numbers of cases per million (CC= 181,231 in Hong Kong as of
August 1, 2022, [20]) probably is connected with much higher values of the tests per case ratio in
mainland China, [14].
     The lack of appropriate testing makes it especially difficult to detect the first cases of a new
disease, which for SARS-CoV-2 probably appeared long before December 2019 [26]. In particular,
theoretical estimates give the date of the appearance of the first case at the beginning of August
2019, [6].
    The insufficient testing and high values of visibility coefficients can lead to controversial
conclusions about the influence of vaccinations. For example, for complete datasets, unexpected
upward trends for CC and DC values with the increasing VC were revealed at the very high
significance level (see rows 18 and 20). Similar correlations were also found in [11] for average
daily numbers of COVID-19 cases and deaths. In some countries (e.g., Israel, Japan, New Zealand),
high vaccination levels did not prevent new severe pandemic waves [10, 14] with record numbers
of cases and deaths, [10, 14]. Statistical studies support the fact that vaccinations diminished CFR,
but their ability to reduce infections should be questioned [10, 11, 13, 14] and needs further
investigation.
    It would also be interesting to investigate the reasons for the increase in CC and DC values with
the increase in incomes (see rows 3 and 6 in Table 1). One of them could be a lower mobility and
less number of contacts in poor countries [18]. The age of population is another important factor in
the visible COVID-19 pandemic dynamics [11, 35], since the percentage of asymptomatic (and
unregistered) patients is much higher in children [27-30]. In particular, a one-year increment in the
median year of population yields a 12-18 thousand increase in CC values and 52-83 increase in DC
values (both figures correspond December 31, 2022), [35]. Taking into account the 24 year
difference in the median age (18 in Africa and 42 in Europe, [36]) we can expect 288- 432 thousand
higher CC figures and 1.2-2 thousand higher DC figures in Europe. The huge number of undetected
COVID-19 cases increases the probability of the appearance of new dangerous SARS-CoV-2
variants.

Conclusions
  Non-linear correlation analysis (using JHU datasets for Europe and Africa corresponding to
August 1, 2022) demonstrated that the numbers of COVID-19 cases CC and deaths DC per capita
and case fatality risks CFR=DC/CC increase for richer countries. The same trends were revealed
for DC and CFR values in Africa, but opposite ones in Europe. As expected, the testing and
vaccination levels increase with the growth of GDP. Higher levels of testing probably allowed
revealing more cases and COVID-19 related deaths in rich countries. CC values showed a very
strong increasing trend with the increase of numbers of tests per capita (TC). Unexpectedly, the
same increasing trend was revealed for CC and DC values versus percentage of fully vaccinated
people (VC). Nevertheless, the decrease of CFR with the increase of VC demonstrates a positive
effect of vaccinations.
   In some countries, the number of undetected COVID-19 cases may be tens or even hundreds of
times higher than the number of registered ones due to the differences in testing levels and age
structure. This fact increases the probability of the appearance of new dangerous SARS-CoV-2
strains and has to be taken into account in further investigations of impact of different factors on
the pandemic dynamics.

Conflict of Interest
The authors declare no conflict of interests

Ethical Approval statement
   The study does not use any experiments with humans or animals. The data sources are available
on the Internet.

Acknowledgments
   The authors are grateful to Robin Thompson, Matt Keeling, and Paul Brown for their support
and providing very useful information. Igor Nesteruk was supported by INI-LMS Solidarity
Programme at the University of Warwick, UK.



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[36] https://www.visualcapitalist.com/mapped-the-median-age-of-every-continent/.        Retrieved
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Supplementary tables
   Table S1. Gross domestic product per capita (GDP) based on purchasing power parity
(PPP), accumulated and daily characteristics of the COVID-19 pandemic dynamics in
African countries as of August 1, 2022 (figures corresponding to other days are specified
in notes).

     Country           GDP             People           Total            Total           Total

                    (PPP) per         fully          cases per      deaths per        tests per

                    capita         vaccinated      million CC,     million, DC,      thousand

                    Int$, [19]    per hundred,         [20]             [20]          TC*1000,

                                   %, VC, [20]                                          [20]

 Algeria               13002         15.5111         6056.096         155.643          no data

 Angola                7360          22.1427         2964.922         55.414           46.9113

 Benin                 4137          20.6628         2101.733         12.541           no data

 Botswana              19287         58.4427         125740.7         1070.15          882.8399

 Burkina               2663          7.6429          955.989          17.511           14.6954
Faso

Burundi      856     0.1327    3609.85    3.028      128.37718

Cameroon     4398    4.5123    4419.892   70.996     100.41618

Cape         7740    52.427    105732.9   697.368    no data

Verde

Central      1102    22.8223   2705.44    20.707     17.36418

African

Republic

Chad         1705    21.0128   432.894    11.234     12.7419

Comoros      3355    46.525    10120.18   194.736    122.0629

Congo        4578    11.2125   4245.343   66.143     67.6927

Cote         6345    30.4627   3106.748   29.514     56.07519

D'Ivoire

Democratic   1316    2.5827    961.196    14.495     10.89919

Republic

of Congo

Djibouti     6667    17.2524   14191.94   170.955    280.15911

Egypt        14928   35.3324   4719.337   226.657    109.4157



Equatorial   19036   13.0923   10242.49   111.963    296.4616

Guinea

Eritrea      2101    No data   2777.109   28.451     6.5443

Eswatini     10411   28.6927   61464.21   1188.488   461.01619

Ethiopia     3407    30.5225   4092.664   62.918     41.77419

Gabon        17848   10.9828   20720.76   130.703    683.37418

Gambia       2646    13.5427   4575.146   139.398    58.9746

Ghana        6754    24.425    5120.666   44.376     75.08418

Guinea       3029    18.9828   2764.429   32.885     52.35119
Guinea-        2784    17.5328   4082.066   83.466     69.36819

Bissau

Kenya          6061    17.6529   6369.872   107.008    70.33519

Lesotho        3034    38.2522   14920.31   307.699    201.50818

Liberia        1779    44.8321   1451.453   56.61      26.9235

Libya          18345   18.1126   74772.13   954.823    no data

Madagascar     1778    4.6427    2299.481   48.693     15.62316

Malawi         1603    9.7227    4395.482   134.089    29.62819

Mali           2575    6.8427    1425.612   33.737     32.32619

Mauritania     6920    30.5623   13559.99   214.952    216.28619

Mauritius      25043   75.2727   188503.5   779.882    987.5818

Morocco        9041    63.2924   34014.06   437.958    316.60614

Mozambique     1439    39.9228   7157.792   69.052     41.8319

Namibia        10448   19.0725   66894.43   1609.39    417.38419

Niger          1435    11.8325   360.516    12.316     10.0810

Nigeria        5853    13.228    1222.94    14.747     24.7419

Rwanda         2808    77.9127   9823.436   108.9      411.15520

Sao Tome       4681    45.125    27408.37   336.162    21.03917

and Principe

Senegal        4093    6.35      5180.094   116.61     65.3038

Seychelles     35272   76.1227   426683.6   1577.909   no data

Sierra Leone   1958    25.7727   918.457    14.844     50.88914

Somalia        1322    11.9624   1583.304   79.751     29.3720

South Africa   15361   32.3526   67435.12   1717.093   431.66719

South Sudan    928     13.6927   1649.847   12.839     38.17218

Sudan          4442    9.9412    1379.979   108.57     12.331

Tanzania       3358    23.2427   589.888    13.226     7.1682

Togo           2599    16.4928   4406.334   32.274     86.72219
 Tunisia                                12300                       52.0226          92040.93         2368.191          379.01314

 Uganda                                 2961                        27.1227          3691.081         79.121            59.95519

 Zambia                                 3776                        26.49            16919.88         206.182           180.45615

 Zimbabwe                               2523                        29.35            16030.36         348.704           148.80419
     Figures corresponding to different days in 2022:
     February: 1 – 13; 2– 18;
     March: 3 -7; 4 -10; 5 -12; 6 -24;
     May: 7 -1; 8 -5; 9 -18; 10 -19; 11 -29; 12 -30;
     June: 13 -2; 14 -12; 15 -15; 16 -16; 17 -19; 18 -20; 19 -22; 20 -23;
     July: 21 -3; 22 -17; 23 -24; 24 -27; 25 -31;
     August: 26 -2; 27 -7; 28 -14; 29 -21.




   Table S2. Gross domestic product per capita (GDP) based on purchasing power parity
(PPP), accumulated and daily characteristics of the COVID-19 pandemic dynamics in
European countries as of August 1, 2022 (figures corresponding to other days are
specified in notes)


   Country                           GDP (PPP)                              People      Total cases             Total         Total tests

                                  per capita                                fully     per million       deaths per        per thousand

                                   Int$, [19]                        vaccinated          CC, [20]         million,        TC*1000, [20]

                                                                   per hundred,                            DC, [20]

                                                                     %, VC, [20]

 Albania                            17.383                              43.9733        109424.4           1242.858           565.33626

 Andorra                            63.600                              67.6637        575802.8           1935.876           3799.7197

 Austria                            64.751                              76.445         535081.7           2277.159           21272.1327

 Belarus                            21.686                              66.5233        103781.5           743.148            1380.27312

 Belgium                            61.587                              78.85          381107.7           2778.558           2955.33223

 Bosnia and                         17.471                              25.874         117815.3           4849.366           458.372

 Herzegovina

 Bulgaria                           28.593                              29.99          175689.8           5431.995           1463.89826

 Croatia                            36.201                              55.3331        292302.4           4021.049           1212.4527

 Cyprus                             48.443                              72.0330        628244             1244.41            32925.8311

 Czechia                            47.527                              65.49          379468.8           3853.198           5193.48826

 Denmark                            69.273                              81.69          552355.7           1139.516           11043.2626
Estonia         44.778    63.5      441332.6   1971.851   2577.75725

Finland         58.010    78.3735   211531     905.348    1994.02224

France          56.036    78.63     503224.3   2258.135   4126.75422

Germany         63.271    76.01     371147.5   1728.24    1574.02119

Greece          35.596    73.08     416397.4   2967.728   8088.1226

Hungary         40.944    63.8634   202422.7   4818.85    1127.08113

Iceland         64.621    78.3610   545876     483.346    3709.57424

Ireland         124.596   81.18     329721.7   1539.148   2476.13527

Italy           50.216    80.95     355493.4   2906.922   3795.99826

Kosovo          13.964    46.25     142944.2   1779.346   1036.05325

Latvia          37.330    69.6929   461241.4   3146.347   3876.13726

Liechtenstein   No data   67.7232   479341.2   2202.925   2321.5763

Lithuania       46.479    67.37     424716.3   3304.684   3128.55323

Luxembourg      140.694   No data   441487.1   1734.653   6725.73125

Malta           54.647    89.28     214294.1   1507.362   3703.58926

Moldova         16.719    34.7417   173831.8   3791.598   no data

Monaco          No data   69.961    385133.3   1662.76    no data

Montenegro      24.878    45.27     414061.1   4376.779   no data

Netherlands     68.572    68.3532   477054.9   1290.389   1753.39324

North           19.726    39.8233   156028.8   4456.267   986.11826

Macedonia

Norway          77.808    74.96     269485.9   670.551    2064.50525

Poland          41.685    58.81     158461     3042.989   964.88120

Portugal        40.805    86.5432   519445     2392.882   4161.80816

Romania         36.622    41.9818   158772.8   3415.205   1099.9469

San Marino      70.139    70.0315   589403.2   3496.711   no data

Serbia          23.904    47.7127   309830.7   2370.063   1433.86926

Slovakia        38.620    50.7333   473844     3712.996   9405.6626

Slovenia        48.534    57.6728   511303.1   3161.257   2517.85826

Spain           46.413    85.5335   278530.9   2331.568   1961.84821
 Sweden                            62.926                         73.1936                        242638     1849.414   1758.61423

 Switzerland                       84.658                         69.12                          454386.7   1598.245   2448.13524

 Ukraine                           14.325                         34.818                         121631.5   2675.378   443.1016

 United                            55.301                         75.11                          346375.1   3035.892   7480.12114

 Kingdom

 Vatican City                      No data                        No data                        56751.47   No data    no data

  Figures corresponding to different days:
  1 -December, 21, 2021;

  in 2022:
  January: 2 -5; 3 -10; 4 -29; 5 -31;
  February: 6 -18; 7 -23; 8 -27;
  March: 9 -10; 10 -29;
  April: 11 -14;
  May: 12 -10; 13 -11; 14 -19; 15 -22;
  June: 16 -1; 17 -2; 18 -11; 19 -12; 20 -16; 21 -17; 22 -18; 23 -19; 24 -20; 25 -21; 26 -22; 27 -23;
  July: 28 -5; 29 -11; 30 -26; 31 -28; 32 -29; 33 -31;
  August: 34 -2; 35 -3; 36 -11; 37 -21.




  Fisher function

       The experimental values of the Fisher function can be calculated with the use of the formula:
                                                                               r 2 ( n - m)
                                                                    F=
                                                                            (1 - r 2 )(m - 1)
                                                                                        (S1)
where n is the number of observations (number of countries and regions taken for statistical
analysis); m=2 is the number of parameters in the linear regression equation (2), [22].