The number of 60-year-olds and over moved from 833,000 to 2.4 million over the reporting period, an annual rise of 2.3%, the HCP said in a statement on the occasion of the International Day of Older Persons, celebrated on 1 October.
The Day is celebrated this year under the theme "Older persons and the achievement of the MDGs".
It added that it forecasts the number of older persons to grow by 3.5% yearly between now and 2030, compared to 0.9% for overall population, to reach 5.8 million by 2030.
This, it continued, accounts for 15.4% of the population as against 8.1% now.
The statement noted that the average number of children per woman declined from 7.2 to 2.4 between the start of the 1960s and 2010, which resulted in population ageing.