Is it because of good health care and/or high living costs?

This is from the article, Our Pro-poor health care policy rewarded, by Professor Chula Goonasekera in The Island Online.

We are a tropical country with a 20 million population. Its birth rate and death rate are reducing with a reduction in population growth. Currently life expectancy in Sri Lanka is estimated to be 68 for males and 75 for females. As a result, our population pyramid had now begun to invert and Sri Lanka is expected to be the third oldest country in Asia after Japan and Singapore by 2010 in the Asian region. Unfortunately, to date, we are yet to pay sufficient attention to care for our increasingly aged population.

Find Singapore here.