Introduction 
In the last two decades, humanity has faced an unprecedented number of crises, including financial, economic, environmental, social, and political crises, such as increasing unemployment, food shortages and price increases, increased pressure on financial institutions, insecurity, and political instability in cities (UN-HABITAT, 2012). Cities, and especially metropolises, are complex systems consisting of various dimensions, facing various challenges in the path of development, the place of realization of public interest and basic and essential human needs, as well as responding to the material and non-material needs of individuals (United Nations, 2017). Urban changes are a continuous process involving various spatial transformations in the city (Wong, 2014). Therefore, it is necessary to continuously measure, evaluate, and explain these changes in various dimensions of cities.
Due to the rapid urban growth process and the problems that have arisen, experts and planners have relied on various indicators to measure urban development; these indicators have often been proposed economically (Sarrafi & Hashemi, 2018). However, due to their reductionist shortcomings, addressing development as a complex, multidimensional, and not merely economic matter, and also the importance of sustainability and community-based perspectives in measuring development, alternative indicators have been considered ((Sarrafi & Hashemi, 2018) (WIJAYA, 2019), (Discoli et al., 2014), (Rogerson, Findlay, Morris, & Coombes, 1989)). Following this change in perspectives, urban development is no longer simply an economic matter but also introduced as a political and social phenomenon that pursues human-centered goals such as freedom, justice, prosperity, and well-being (Bakker, Verburg, & van Vliet, 2021). In recent decades, the limitations of one-sided and one-dimensional indicators have been considered, and with the concern for the sustainability of urban development, combined and multilateral or holistic indicators have been used more often to overcome the aforementioned limitations. One of these development measurement indicators was introduced by the United Nations Human Settlements Program in its 2012 report as the City Prosperity Index (UN-HABITAT, 2012 (Bonaiuto, Fornara, Ariccio, Cancellieri, & Rahimi, 2015)). This index examines, evaluates, and monitors the city in 6 main dimensions as follows:
• Productivity
• Infrastructure
• Quality of Life
• Environmental Sustainability
• Equity and Social Inclusion
• Urban Governance and Legislation
The present study was conducted in an attempt to answer the following questions:
What is the comparative status of the 22 districts of Tehran Municipality in terms of the dimensions of the city prosperity index in 2016, 2011, and 2012?
What are the strengths and weaknesses of the districts in terms of the city prosperity index?
Materials and Methods
In the present study, the research philosophy is post-positivist and quantitative in nature, with an inductive selective approach, a case study strategy, and a longitudinal time horizon, which uses various techniques and methods to collect data in each section of the research. For example, to collect the data required for the theoretical foundations, research background, and review of experiences, documentary and library methods were used using various plans, articles, documents, reports, and books. Finally, to collect the data required for the main and secondary dimensions of the city prosperity index and to evaluate and compare the 22 districts of Tehran Municipality, mainly secondary data derived from the results of the population and housing census in 2011 to date, spatial and archival data were used.
For deeper analysis and spatial analysis of variables related to the main and sub-dimensions of the urban prosperity index in the 22 districts of Tehran Municipality, in order to create a spatial database for producing, modifying, storing, maintaining, and managing spatial data, as well as performing spatial analyses and applying statistical tools, ArcGIS software has been used.
Finally, with the amendments made to the initial theoretical framework and the addition or replacement of new indicators according to the data base of the Tehran metropolis and the suitability of the new data with the urban prosperity index, the final operational framework of the research has been developed, which ultimately has six main dimensions, 15 sub-dimensions, and 30 indicators.
Findings
After collecting the necessary data and information to examine the prosperity index in the 22 regions of Tehran, in this section, the results and findings after standardizing the data, the final city prosperity index for the 22 regions and the time periods of 1390, 1395 and 1400 have been calculated and classified into very strong, strong, medium strong, medium, weak.
The research findings indicate that, in general, the level of urban prosperity in the 22 regions of the Tehran metropolis is in the weak to medium strong range, and there are no strong and very strong levels among the regions of Tehran in the years in question. Among them, only regions 1, 2, 4, 5 and 6 have experienced medium-strong prosperity in some years, and other regions have had medium and weak prosperity in all years. The best flowering status in the period 90 to 1400 is related to regions 5 and 1 in 90, followed by regions 6 and 2 in 95 and region 4 in 90.
On the other hand, regions 8, 9, 13, 14, 16, 17, 18, 21, and 22 have experienced poor flowering throughout the entire period under study, and it can be said that regions 9 and 21 of Tehran Municipality are in a more unfavorable situation in terms of flowering compared to other regions.
The average urban prosperity scores among different regions in these years show that from 2011 to 2016, the prosperity level in Tehran’s regions decreased, but in the period from 2016 to 2017, it increased.
In order to diagnose and analyze in more depth the strengths and weaknesses of the regions from the perspective of the urban prosperity index based on the data of the last year of the study (2016), the situation of each region can be analyzed in more detail. In addition to the final scores examined in the previous section, the strengths and weaknesses of the 22 regions of the municipality can be clearly stated from the perspective of the urban prosperity index.
Conclusion
In this section, in order to conclude, it can be stated that the proposed framework for measuring CPI in Tehran and the time steps under study, despite all its limitations, has sufficient efficiency and implementation potential and can be the basis for providing a comprehensive analysis of the comparative situation of the 22 regions of Tehran Municipality as well as prioritizing intervention in order to achieve multifaceted and sustainable development. One of the major limitations of the research is access to data sources. However, despite all the limitations and shortcomings in the available data sources, the gap between it and the required data sources has not been so great that the CPI measurement framework has lost its efficiency, and its implementation in Tehran is not possible. Given the poor condition of most regions in terms of the city prosperity index, we need serious measures in the city of Tehran to improve the welfare and quality of life of citizens. According to the analytical maps provided, the southern and western regions of Tehran can be given higher priority for intervention and planning.
To prioritize intervention to improve the condition of the regions, the ranking of the last year of the study can be used, and regions nine, twenty-one, seventeen, twenty-two, and ten, respectively, are introduced as the first five priorities for planning to improve the rank and living conditions of citizens. Finally, it should be noted that based on the strengths and weaknesses of the regions in terms of the city prosperity index, despite the observation of a poor condition in most of the 22 regions of the Tehran Municipality, with a case-by-case, separate and more detailed examination of data related to the main dimensions, there are also strengths, and stating a poor condition does not mean weakness in all cases and dimensions of the region. This is also true from another perspective: when a region has a relatively better score than other regions, it does not necessarily mean strength in all its sectors, and we may still see sectors and dimensions with weaker values.
As a result, it can be stated that by using the analyses carried out to identify the strengths and weaknesses of regions from the perspective of the city prosperity index, regional managers can adopt basic strategies to maintain and improve the stronger dimensions and sectors, as well as fundamentally correct and strengthen the weaker dimensions and sectors of their region.