My work on human capital began with an effort to calculate both private and social rates of return to men, women, blacks, and other groups from investments in different levels of education.

青竹 云海 晨光 星夜 荷风 晴雪 秋山 听海 沙丘 森语 梅影 花野 听雨 晴窗 暮色 橘光