WASHINGTON, D.C. - Initial projections show that 9 percent of the Colorado population lacks health insurance in the wake of the implementation of the Affordable Care Act, according to a study released today by WalletHub, a subsidiary of Washington, D.C.-based Evolution Finance.

Before the law's implementation, according to the study, the uninsured rate in Colorado was 16.5 percent.

The study subtracts the number of new Medicaid enrollees and the number of newly insured under private-insurance plans from the number of uninsured before the law was implemented.

Opponents of the Affordable Care Act have often pointed out that no one knows the true number of uninsured in any state, because there is no way to determine how many people who bought coverage under the law's new mandates, such as health-insurance exchanges, had coverage before.

For example, at Colorado's exchange, Connect for Health Colorado, the questionnaire answered by consumers purchasing included a question asking whether or not the consumer was previously insured, but that question was optional.

For this reason, Connect for Health Colorado officials do not have clear information about how many people who signed up through the exchange were uninsured before.

Methodologies by different analytics companies and health-care organizations also have disagreed on the percentage of uninsured following the law's implementation.

Analytics company RAND Corp. estimates that 28 percent of those who obtained coverage under the Affordable Care Act were uninsured previously, while the U.S. Department of Health and Human Services placed its estimate at 87 percent.

WalletHub used a middle-of-the-road number calculated by Kaiser Family Foundation, 57 percent, because it is based on a nationally representative sample and spans the appropriate time period, according to the study.