Updated

The Boy Scouts of America says its membership fell by 6 percent in 2013, a year in which the organization announced it would begin to accept openly gay youth.

BSA spokesman Deron Smith said Wednesday that it was "impossible to point to any single factor" for the drop, which is slightly higher than in some previous years over the last decade.

Scouting leadership voted in May to open its doors to openly gay youth while continuing to exclude openly gay adult volunteers. The change was supported by BSA's top leadership and lauded by gay-rights groups, but angered social conservatives and some church-based scout troops.

BSA still has nearly 2.5 million youth members and almost 1 million adults.