BERLIN (AP) — Migrant mothers helped boost Germany's fertility rate to a 33-year high last year.

The Federal Statistical Office reported Monday that Germany's overall fertility rate rose to 1.50 children per woman in 2015, compared with 1.47 the previous year.

The 2015 rate was the highest since 1982, when the figure stood at 1.51.

New data show that women with German citizenship had a fertility rate of 1.43, up from 1.42 in 2014.

Women with foreign citizenship had a fertility rate of 1.96 in 2015, compared with 1.86 the previous year.

The country of 80 million recorded an influx of almost 900,000 asylum seekers last year. Most were fleeing hardship in Africa, Asia and the Middle East.

A fertility rate of 2.1 is needed to keep populations stable.