CREATE TABLE table_21169 ("Date of Sterilization" TEXT, "Age 10-19" FLOAT, "Age 20-29" FLOAT, "Age 30-39" FLOAT, "Age 40-49" FLOAT, "Age 50-59" FLOAT, "Age Unknown" FLOAT, "Total" FLOAT)

Name the least age 40-49
SELECT MIN("Age 40-49") FROM table_21169
SELECT MIN("Age 40-49") FROM "table_21169"