We document stark differences in the labor market outcomes between the U.S. and China, the largest two economies in the world, during the past 30 years. (1) The peak age in cross-sectional age-earnings profiles stays constant at around 45-50 years old in the U.S. but decreases sharply from 50 to 35 years old in China. (2) Age-specific labor earnings grow drastically in China but almost stagnate in the U.S. (3) The cross-sectional and life-cycle age-earnings profiles look remarkably similar in the U.S. but differ substantially in China. We provide a unified decomposition framework to infer life cycle human capital accumulation, inter-cohort human capital growth, and human capital price changes from repeated cross-sectional data and address the above facts. We apply the framework to several applications.