Annual growth in GDP/adult in Japan has declined from over 10% in 1969 to an average of 1% since the financial crisis in 1991. I show that a dynamic Solow growth model, augmented with human capital, weekly labor-hours, and oil prices, explains Japan’s annual growth rates from 1969 to 2007 as conditional convergence to a steady-state rate of 1%/year. Each additional year of average adult schooling attainment raised GDP/adult directly and indirectly by 20 percent, and weekly hours worked had an output elasticity of 0.5. The marginal product of schooling was double the marginal product of physical capital.