According to the Basic Resident Register data, foreign residents in their 20s increased by 680,000 to 1.22 million over a 10-year period through 2025, while Japanese in their 20s decreased by 1.03 million to 11.64 million. By prefecture, Gunma had the highest proportion of foreigners in their 20s with 14.1%, followed by Gifu and Ibaraki. Nine others, including Tokyo, Osaka and Kyoto, exceeded 10%. Foreigners are becoming increasingly important not only in the labor market but also as contributors to Japan's social security system. Across all age groups, foreign residents accounted for 3.0% of the Japanese population in 2025. As of the end of June 2025, the largest foreign resident population was from China, at about 900,000, followed by Vietnam, with about 660,000, according to the data.