New Census Bureau health insurance figures suggest that the number of U.S. residents in employer-sponsored plans plunged 3.7% between 2008 and 2009.
The number fell of people in private employer-sponsored plans fell to a little below 170 million in 2009, according to census figures.
The group plan enrollment number fluctuated between 175 million and 
180 million from 2000 to 2008, and, before that period, it had not been below 170 million since 1997, when the Census Bureau found about 166 million people in group health plans.
The share of the 304 million U.S. residents covered by private employer-sponsored plans fell to 55.8% in 2009, down from 58.5% the year before. The Census Bureau began recording detailed health insurance enrollment figures in 1987. In 2009, the share of the U.S. population in employer-sponsored plans dropped to the lowest level the bureau has recorded during that period.
The share started at 62.1% in 1987 and was above 60% in most years up until 2005. The bureau recorded a small drop between 2005 and 2006, and an accelerating rate of decline in subsequent years.
The only year when the percentage-point drop in employer plans' share of the total market was as severe as it was between 2008 and 2009 came during the recession year of 1991, when the share dropped to
59.7%, from 60.4%
