The Hong Kong population's pace of ageing is increasing as post-war baby boomers enter old age.
Announcing the results of 2016 Population By-census today, Commissioner for Census & Statistics Leslie Tang said the median age increased from 39.6 in 2006 to 43.4 last year.
He expressed concern over the ageing trend, saying the largest population is in the 50 to 59 age group.
"Twenty years later they will become 70 to 79. The children when they grow up, they cannot supplement the labour force. That worries me.
"We will have less labour force to support the elderly. This is what I refer to as a demographic challenge for Hong Kong."
The resident population was over 7.3 million at the end of June, up by 260,000 people on 2011.
Excluding foreign domestic helpers, the sex ratio dropped from 961 males per 1,000 females in 2006 to 925 males in 2016.
The sex ratio of more females to males applies to all age groups, except for the under-25 population.
The working population in 2016 was 3.8 million, earning a median monthly income of $15,000, up 50% on 2006.
The median domestic household monthly income was $25,000, up 45% over the same period.
