KUNMING, CHINA - DECEMBER 12:  A senior citizen takes a walk in the yard of the Happy Times Nursing Home on December 12, 2007 in Kunming of Yunnan Province, China. Two-thirds of the elederly residents in the nursing home suffer from senile dementia. China's population is ageing; with currently over 140 million elderly citizens, the figure is expected to grow at an annual rate of about 3.2 percent in the next 50 years. Getty Images logo Getty Images 24 months ago

KUNMING, CHINA - DECEMBER 12: A senior citizen takes a walk in the yard of the Happy Times Nursing Home on December 12, 2007 in Kunming of Yunnan Province, China. Two-thirds of the elederly residents in the nursing home suffer from senile dementia. China's population is ageing; with currently over 140 million elderly citizens, the figure is expected to grow at an annual rate of about 3.2 percent in the next 50 years.