Wiesbaden, Germany  - The number of same-sex couples in Germany has nearly doubled in a decade to 68,000, according to census data from federal statisticians in Wiesbaden on Tuesday.

The 2007 tally of homosexual people living permanently together marked an increase of 30,000 from 11 years earlier.

The data was gathered in a micro-census, an annual survey of an exactly chosen sample of Germans.

Statisticians cautioned that the number might under-represent same-sex couples, since it was optional for households to answer the question and questionnaires were tallied even if they gave no data on the issue.

The apparent change might also be misleading, since it was possible that couples had simply become more willing during the decade to reveal their situation to the pollsters.

Germany has about 15,000 legally registered same-sex partnerships. So-called gay marriages became legal in Germany in 2001. About two thirds of the registered partnerships are between men. (dpa)