Why did Mexican migration to the U.S. change drastically in the 1930?

Mexican migration to the U.S. changed drastically in the 1930s primarily due to the Great Depression, which led to widespread unemployment and economic hardship in both countries. The U.S. government implemented repatriation programs that aimed to deport Mexican immigrants and their U.S.-born children, often regardless of their legal status. Additionally, anti-immigrant sentiment and fears of job competition intensified during this period, further discouraging migration. As a result, the flow of Mexican migrants significantly decreased during the 1930s compared to previous decades.