According to data gathered by the King County Department of Health, more than 500 people between the ages of 18 and 64 on Mercer Island were counted as being without health care insurance between 2009 and 2011.

This and other data from the American Community Survey, taken between 2009 and 2011 in towns and cities throughout King County, were released earlier this summer.

Countywide, the agency estimates that 210,000 of all adults between 18 and 64 are without health care insurance, an amount that represents more than one-third of the total adult population between 18 and 64 years old, and 6 percent of the total county population.

The agency has been gathering this information and other data as it readies to help county residents to transition to the Affordable Care Act (ACA). The most important aspect of the ACA is the requirement that most individuals in the United States must have health coverage beginning Jan. 1, 2014.

Beginning Jan. 1, 2014, new coverage options are expected to be available in Washington state through expansion of the Medicaid program and Washington Healthplanfinder, our state’s Health Benefit Exchange.