NU Online News Service, Nov. 12, 3:53 p.m. – The number of operating U.S. health maintenance organization plans fell 13% between 2000 and 2001, to 542, according to Aventis Pharmaceuticals, Bridgewater, N.J., a subsidiary of Aventis S.A., Strasbourg, France.

The drop was the third consecutive annual decline, Aventis says.

Data compiled for Aventis by SMG Marketing-Verispan L.L.C., Chicago, shows the number of HMO plans reached a peak of 902 in 1998 before falling to 820 in 1999.