TAIPEI -- Taiwan's total population may decline in 2020 due to a falling birth rate, two years earlier than a previous forecast, according to the island's development planning department.

The number of newborns is very much likely to be fewer than that of the deceased this year, leading to a natural decline of the population, the department said in a report published earlier this week.

The island may become a super-aged society by 2025, meaning that one in five citizens w

ill be aged over 65, one year earlier than the previous estimate, the report added.

The earlier arrival of a super-aged society and population decline will pose serious challenges to Taiwan's labor force, taxation, and pension system.

The island has been gearing up to tackle the changes in population with a variety of approaches, including boosting the country's fertility rate, strengthening the labor force structure, and improving care for senior citizens, the department said.