Of Rice and Men: Rice Consumption-Based Estimates of Undocumented Persons in Malaysia

Quantifying undocumented populations is a persistent challenge globally. A shortage of reliable estimates limits analysis of unauthorized migrations, effective policy responses, and measures to counter anecdote-fueled immigration debates. Malaysia exemplifies the struggles of geographically exposed and institutionally constrained countries attempting to manage undocumented migration through policies based on limited data and little evaluation. To provide time series data enabling migration policy analysis and to contribute an innovative methodological approach, this article estimated Malaysia's undocumented population since 1963 by modeling the relationship between rice consumption per capita and economic development. The modeled relationship, together with known rice consumption patterns, implies an undocumented population of 2.62.75 million in 1963 and 6.288.24 million in 2017. These findings suggest that existing unauthorized migration estimation methods produce significant undercounts and that Malaysia's hidden population is much larger than believed. They also demonstrate the potential for consumption-based methods to address undocumented population data gaps globally.