In terms of marital status of the population 20 years old and over in 2007, there are 4,841 single or 20.2% of the total population of the age range which is 24,016. There are more single males than females with a ratio of 183 males per 100 females. Sixty percent of those 20 years old and over is married, 8.2% is widowed, 1.6% is divorced/separated, 9.8% is common-law/live-in and 0.2% is of unknown marital status.
Irosin population has grown from 8,644 in 1903 to 56,662 in 2015 with a cumulative increase of 48,018 or 556%. Within the span of 112 years the population rose at an annual average rate of 1.68% per year. The population has practically doubled from the 1970 population to the present 2015 population or 45 years. The growth rate for the census period 2010 and 2015 is 1.72%. At this present growth rate, the doubling time of population is 40 years.
Population Composition Irosin has a total population of 56,662 in 2015, comprising 7.1% of Sorsogon province total population. There are 11,820 documented households for the same year and the average household size is 4.64. The population has grown by 4,885 persons from 2010 with an average annual growth rate of 1.72%.