Life quality as an indicator of sustainable development: international statistical research

The purpose of the article is to substantiate the methodology for determining the European quality of life index. The theoretical and methodological basis of research is the ideas of the interdependence of life quality and sustainable development. To achieve the desired goal, the following research methods were used: analysis and synthesis (for determining theoretical and practical aspects of ensuring the life quality); statistical (for determining standardized indicators and a European Quality of Life Index for Sweden and Ukraine); abstractlogical (for theoretical summarization and conclusion). As a result, the authors created the European Quality of Life Index based on the comparison of the characteristics of international life quality assessment systems (calculation principle, number and composition of indicators, number of countries covered for calculation), as well as systematization of research by Ukrainian and foreign authors. Therefore, the authors selected twelve main indicators. The indicators are divided into two groups: stimulants (prosperity index, basic human needs index, welfare bases, availability of nutrition and basic health care, GDP per capita, population, global competitiveness index, personal security, access to basic knowledge, ecosystem status) and disincentive (government debt, unemployment). To determine the “European life quality index”, the authors used the formula for calculating the arithmetic mean, as all selected indicators can be considered equivalent as a result of standardization by the method of “minimummaximum”. In addition, for in-depth analysis, the authors calculated the growth rates of indicators, as well as coefficients of variation. The authors made calculations based on data of 2013–2019 for two countries, namely Sweden and Ukraine. Sweden occupies a much better position in achieving the Sustainable Development Goals, so studying the impact of life quality on sustainable development in this country will suggest ways to achieve the chosen strategic priorities for Ukraine.


Introduction.
Quality of life can be defined in many ways, that is why it is the center of sociological, economic and political research. For the vast majority of countries, quality of life is a key indicator of sustainable development being «as a desired outcome of service delivery in mainstream and special needs education, health care, social services (particularly for disabled and elderly people) and, increasingly, for crosscutting public sector partnership policy at all levels» (Galloway, 2005). In addition, the UN Sustainable Development Goals (UN, 2020) also work in a spirit of partnership and pragmatism, and aim at the right choice in order to steadily improve the quality of life for future generations.
According to scientists, measuring the life quality in a behavioral economy is much more complicated (Glonti, 2020;Nenkov, 2017). In the context of globalization and digitalization, the priorities of countries' development and the tools to achieve them continue changing. That is why much attention is paid to the social, cultural and environmental living conditions of the population of European countries (Chernega, 2019;Khomenko, 2019;Sushchenko, 2019). At the same time, the existence of democratic mechanisms for the transformation of society (Calinescu, 2018), social dialogue (Calinescu, 2017), a sufficient level of education of the population (Sitnicki, 2018;, a developed and powerful education system contribute to the processes of improving the quality of life of the population (Kasych, 2018;Sitnicki, 2020). At the same time, economic factors do not lose their relevance, in particular innovation (Kasych, 2017;Khovrak, 2013), and financial stability of enterprises (Polinkevych, 2016). The economic growth of the state is closely linked to the population life quality (Kaigorodova, 2018). It is also worth remembering that "interpersonal sensitivity and social support satisfaction predicted quality of life" (Wedgeworth, 2017). The empirical studies prove a direct correlation between starting a business and quality of life for late-career individuals (Kautonen, 2017). At that time, workspace design and environmental features effects on an employee's morale and productivity, which, in turn, affects the Quality of Life (Vischer, 2017). The concept of Quality of Life is significantly impacting research and service delivery in the field related developmental disabilities (Schalock, 2016). Therefore, all the factors that affect the level and Quality of Life of the population should be divided into groups depending on the level of influence: internal (personal characteristics of a person; the desire to work, the level of education, qualifications and income), family (material resources and social status of the family) and external (influence of society, market and state regulatory mechanisms: natural, economic, state managerial mechanism, social, medical prerequisites, etc.). As a result of these changes, society needs to strengthen social responsibility (Glonti, 2020), awareness of the transformation of development priorities of countries (Calinescu, 2018;Onyshchenko, 2020), as well as an effective system of strategic management (Buzko, 2019;Maslak, 2018) and training of highly qualified professionals (Pochtovyuk, 2017;Polishchuk, 2019). The purpose of the article is to substantiate the methodology for determining the European life quality index.

Materials and methods of research.
Research methods: analysis and synthesis (for determining theoretical and practical aspects of ensuring the quality of life); statistical (for determining standardized indicators and a European Life Quality Index for Sweden and Ukraine); abstract-logical (for theoretical summarization and conclusion). The importance of this paper is confirmed by the review and analysis of scientific publications.
Quality of life can be measured by a set of features that can be weighted by some metric that reflect "well-being", "social welfare" or "sustainable development" (Slottje, 2019). At the same time, the vast majority of scientific publications closely link such concepts as Health, Health-Related Quality of Life, and Quality of Life (Karimi, 2016). The main quality of life assessment systems and indices are the EIU Life Quality Index, the methodology of the European Statistical System Committee, the Better Life Initiative, the International Living Life Quality Index, and the general methodological concept of standards and quality of life (Table 1 (Measuring the life quality in Ukraine, 2013)). The systems shown in Table 1, have different indicators, index calculation methods and the number of covered countries. Therefore, we selected twelve main indicators, which were used to obtain a standardized assessment of each indicator and to calculate the life quality index in 2013-2019 for the two countries, namely Sweden and Ukraine. Sweden occupies a much better position in achieving the Sustainable Development Goals, so studying the impact of life quality on sustainable development in this country will suggest the ways to achieve the chosen strategical priorities for Ukraine.
The calculation of indicators according to the proposed methodology was based on open statistics on the socio-economic development of countries (Global Competitiveness Index, 2019; Social Progress Index, 2019; Statistics of the countries of the world, 2019).
To calculate the European Quality of Life Index, we have chosen a method based on the magnitude of variation. The indicators are divided into two groups: stimulants (prosperity index, basic human needs index, welfare bases, availability of nutrition and basic health care, GDP per capita, population, global competitiveness index, personal security, access to basic knowledge, ecosystem status) and disincentive (government debt, unemployment). "The prosperity index" is marked as , "basic human needs index"as , "welfare bases" -as , "availability of nutrition and basic medical care" -as , "GDP per capita"as , "population" -as P, "global competitiveness index" -with , "personal security" -as , "access to basic knowledge" -as , "ecosystem status" -as E; "government debt" -as , "unemployment" -as . "European quality of life index" is marked as . The standardized evaluation procedure (X´) was performed using the following formulas: for stimulants: (1) for disincentive: (2) where Х -is the indicator value, min X and max X -are the minimal and maximal values of the sample indicator respectively.
In order to bring standardized estimates of indicators into a generalized European index (Ei), the arithmetic mean formula was used based on the fact that all selected indicators can be considered equivalent to each other: ( 3) where is the number of indicators taken into account, is the segment of the study period and is equal {2013-2019}.
The following synthetic indicators were used for the analysis of indicators of stimulation and disincentive of life quality: "chain growth rate of prosperity index" -, "chain growth rate of basic human needs index" -, "chain growth rate of welfare bases" -, "chain growth rate of availability of nutrition and basic health care" -, "chain growth rate of GDP per capita" -, "chain growth rate of population" -, "chain growth rate of global competitiveness index" -, "chain growth rate of personal security" -, "chain growth rate of access to basic knowledge" -, "chain growth rate of ecosystem status" -, "chain growth rate of government debt" -, "chain growth rate of unemployment" -, "chain growth rate of European quality of life index" -.

Results and their analysis.
As a result of the application of the proposed methodology, standardized values of indicators and the European Quality of Life Index for Sweden (Table  2-3) and Ukraine (Table 4-5) were calculated.  Table 2  In this regard, the increase in the indicator was explained: in 2013 it was 63.61, in 2014-94.59, and in 2019 has gained maximal value -96.39.
According to the Table 3 indicators are defined, summarized by a standardized value , show dynamics to improve life quality index from 0.48 in 2013 to 0.89 in 2017 due to rising socioeconomic indicators, which indicates a better quality of life. Although, in 2019 the value of the indicator =0.83 which indicates a slight decrease in the life quality in Sweden. According to the calculations given in the Table  4 An equally important indicator, which affects the decrease of P is : the level of value of this indicator ranges 7.2-9.7 %. The reduction of the number of industrial enterprises, and as a consequence -the reduction of jobs, the inability to maintain their own families -all this has led to a decrease in fertility and labor migration of young people.   The data given in the Table 5, show the main problems of Ukraine in recent years, such as a decline in the prosperity index of the country, a decline in GDP per capita, a decrease in population, and deteriorating ecosystem status. The reasons for this decline in the social and economic life of the country were the unstable political situation in eastern Ukraine, the worsening of foreign relations with Russia and the loss of markets, the weakening of the country's position in the world market. However, the negative factors have given impetus to raising the level of basic human needs and availability of nutrition and basic medical care, which shows the indicator, which during 2013-2019 showed both negative and positive dynamics of the country's development. As of 2019, the value of indicator was 0.35 (Fig. 1). The results of statistical evaluation of indicators in 2013-2019 are shown in the Table 6.  The results of a statistical study show that the biggest differences between the two countries are observed in such indicators as "GDP per capita", "population", "ecosystem status". Given the relatively high correlation between the index of sustainable development goals and the proposed index (>0.7), it should be argued that there is a close interaction. Considerable attention in Ukraine should be paid, accordingly, to the issue of restoring the country's economic potential, as well as the protection of the natural environment.

Conclusion.
The proposed methodology is universal and provides an opportunity to determine the life quality index for any country, and its application allows to conduct rapid diagnostics and identify trends of further changes in the quality of life of the population. Also, this methodology allows for a comparative analysis of quality of life for selected countries and made it possible to compare the results obtained in dynamics. It is worth adding that the high population life quality is an indicator of sustainable development of the country. That is why active cooperation of the government of the country and the citizens is needed in order to support their own production, improve the infrastructure and create attractive living and working conditions for the population.