In regards to social welfare, the post-war era saw a considerable improvement in insurance for workers and their dependents against the risks of illness, as private insurance programs like Blue Cross and Blue Shield expanded. With the exception of farm and domestic workers, virtually all members of the labor force were covered by Social Security. In 1959, about two-thirds of the factory workers and three-fourths of the office workers were provided with supplemental private pension plans. In addition, 86% of factory workers and 83% of office workers had jobs that covered for hospital insurance while 59% and 61% had additional insurance for doctors. By 1969, the average White family income had risen to $10,953, while the average Black family income lagged behind at $7,255, revealing a continued racial disparity in income among various segments of the American population. The percentage of American students continuing their education after the age of fifteen was also higher than in most other developed countries, with more than 90% of 16-year-olds and around 75% of 17-year-olds in school in 1964–66.