A 2025 research published in Physica A: Statistical Mechanics and its Applications has uncovered a striking mathematical regularity in how population is distributed across the Philippines. By analyzing two decades of census data (2000–2020), researchers Dylan Marcus T. Ordoñez and Rene C. Batac from De La Salle University applied the principles of complexity science to determine if Philippine cities follow the famous Zipf and Pareto laws.

Among other key results, the study identifies a consistent 70-30 rule that has persisted for twenty years: the 70% of population lives in the top 30% of all the cities and municipalities (ranked by decreasing population). These cities and municipalities, in turn, perfectly obey Zipf’s Law [the power-law rank-size plots with unit decay exponent] and the Pareto distribution [the power-law distribution of populations with decay exponent of 2]. These mathematical "laws", which have been observed for other countries for various time periods, suggest an emergent robustness of the observed statistical patterns. In contrast, the bottom 70% of cities, which contain the remaining 30% of the population, show significant deviations from these patterns, likely due to socioeconomic and political constraints that limit how small a city can realistically be.

While these statistical laws have been heavily studied for countries in the global north, the Philippines provides a unique case study as a highly dynamic, archipelagic nation with one of the world's densest urban regions: Metropolitan Manila. The study notes that the Philippines is one of only eight countries expected to drive over half of the world's population increase by 2050.

Beyond theoretical physics, these findings offer practical value for urban planning. By understanding the regimes of acceptability of these laws, policymakers can better picture the urban growth of the various cities in the country, which, in turn, will help them manage the interconnectivity and resource allocation, among others. The consistency of the 70-30 rule suggests that the underlying forces of urbanization in the Philippines are robust, providing a mathematical roadmap for building more sustainable and resilient cities in a rapidly growing socioeconomic landscape. ◼