Hong Kong's population structure is changing faster than almost anywhere else in the world. It took a century for France's senior population to double, but that has almost happened here in just 25 years. In 1981, only 6 per cent of people in this city were aged 60 or above, but that number hit 11 per cent last year.
There are three components in the study of population: deaths, births and migration. Deaths are not a particularly exciting issue because people will die anyway, and the number of deaths is stable.
Migration is a more interesting subject. The city saw a lot of people leaving in the 1980s because of the impending political transition back to Chinese control. The government thought the situation would continue in the 1990s but, as it happened, many people returned from overseas.
Officials did anticipate a drop in Hong Kong's birth rate, but they didn't expect it to decline so much.
Our fertility rate is now 0.966 children per woman - one of the lowest in the world.
The figure is even lower, at about 0.7, if we exclude babies born to visiting mothers from the mainland.