Aging of a giant: a stochastic population forecast for China, 2001-2050

This paper presents a stochastic population forecast for China with a special emphasis on population aging. Stochastic forecasting methods have the advantage of producing a projection of the future population including a probabilistic prediction interval. The socalled scaled model for error was used to quantify the uncertainty attached to the population predictions in this study. Data scarcity was a major problem in the specification of the expected error of the population forecast. Therefore, the error structures estimated for European countries were employed with some modifications taking the large size and heterogeneity of the Chinese population into account. The stochastic forecast confirms the expectation of extremely rapid population aging during the first half of the 21st century in China. The old age dependency ratio (OADR) will increase with certainty. By mid-century, with 80% probability, the OADR will lie between 0.41 and 0.56, with the median of the predictive distribution being 0.48, nearly five-fold its current value of 0.1. In particular, the oldest-old population will grow faster than any other age group. This development has major implications for China: to smoothly adjust current birth control policies to less restrictive ones, strengthen the family support system, and improve the social security system for the elderly.