Journal of Population Association of Iran

Journal of Population Association of Iran

Population Dynamics in Iran and Its Provinces: Analysis of Stable and Nonstable Momentum During 1996-2016

Document Type : Original Article

Authors
1 PhD in Demography, Faculty of Social Sciences, University of Tehran, Tehran, Iran
2 Associate Professor, Department of Demography, Faculty of Social Sciences, University of Tehran, Tehran, Iran
Abstract
This study examines the effects of stable and nonstable momentum on the population dynamics of Iranian provinces between 1996-2016. The analysis is based on census data from 1996 to 2016, fertility and mortality estimates, and the cohort-component projection method. Stable momentum reflects the long-term effects of fertility on age structure and the deviation between stable and stationary age distributions. In contrast, nonstable momentum indicates the temporary effects of recent fertility changes and the deviation of the current age structure from stability. Findings show that Iran’s total population momentum declined from approximately 1.7 in 1996 to 1.3 in 2016. At the provincial level, Sistan and Baluchestan had the highest total momentum (1.9), while Gilan and Tehran had the lowest (1.0). The decrease in total momentum is mainly due to a reduction in stable momentum and a partial shift toward nonstable momentum. The exit of large birth cohorts from childbearing ages has diminished the temporary effect of nonstable momentum, contributing to the overall decline. The results highlight the value of decomposing momentum into stable and nonstable components, offering a clearer understanding of demographic dynamics. This approach provides new insights into how age structure influences population growth, especially in the context of fertility transitions.
Keywords

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Articles in Press, Accepted Manuscript
Available Online from 15 April 2025

  • Receive Date 16 December 2024
  • Revise Date 24 January 2025
  • Accept Date 28 January 2025