United States - Population Ages 15 to 64 for Middle Income Countries was 66.39111 % of Total in January of 2020, according to the United States Federal Reserve. Historically, United States - Population Ages 15 to 64 for Middle Income Countries reached a record high of 66.66736 in January of 2015 and a record low of 55.15964 in January of 1966. Trading Economics provides the current actual value, an historical data chart and related indicators for United States - Population Ages 15 to 64 for Middle Income Countries - last updated from the United States Federal Reserve on April of 2024.