TOKYO (JAPAN NEWS/ANN) - The number of annual births in Japan fell below one million for the first time on record last year, government data showed on Wednesday, underscoring the seriousness of the country's declining birthrate.

There were 981,202 births across the country in 2016, the internal affairs ministry said.

The country's population fell by 308,084, or 0.24 per cent, during 2016 to 125,583,658, marking the eighth straight year of decline and the largest annual decrease.

The data were based on resident registrations.

The number of deaths came to 1,309,515, exceeding that of births for the 10th consecutive year. The natural population decrease, or the number of deaths minus that of births, hit a record high of 328,313.

Six of the nation's 47 prefectures saw population growth, with the steepest increase of 0.60 per cent registered in Tokyo, followed by Okinawa, at 0.31 per cent, and Chiba at 0.12 per cent.

The remaining 41 prefectures experienced population falls. The drop was sharpest in Akita at 1.34 per cent, followed by 1.12 per cent in Aomori and 1.06 per cent in Kochi.

The combined population in the country's three biggest metropolitan areas of Tokyo, Osaka and Nagoya posted a record high of 64,530,258 as of Jan 1, accounting for 51.38 per cent of the total Japanese population. Of the three areas, the population grew only in Tokyo.

The proportion of people aged between 15 and 64, or the productive age group, represented 60.14 per cent of the total, continuing to fall from 69.65 per cent in 1994, when comparable data became available.