Lawmakers on Monday were given drastically reduced estimates of what health care reform would cost New Mexico.

Health consultants blamed a computer error as they provided whittled-down projections of the cost of plans proposed by Gov. Bill Richardson and others.

Human Services Secretary Pam Hyde said the lower spending figures could help persuade lawmakers that "we can do it — and it's actually more doable than you thought it was."

Richardson wants the Legislature, which meets in January, to enact a universal health coverage plan that combines government programs and private insurance. It would require New Mexicans to be insured.

Two weeks ago, legislators were told the governor's proposal would require state government to increase spending by about $75 million in the 2010 budget year. That's in addition to the $880 million the state is already projected to spend on health care that year.

As of Monday, the increased-spending figure in 2010 had been lowered to less than $30 million. And the projected additional cost of the governor's proposal over a five-year period was reduced from the $333 million forecast two weeks ago to about $72 million.

Mathematica Policy Research Inc., which has been studying various reform proposals for the Legislature, blamed a computer error for the earlier, higher figures contained in a draft report.

The error inflated the cost of all the reform plans Mathematica has been reviewing, and the estimates for those other plans were revised downward as well.

The new numbers are still considered preliminary and could be revised again when Mathematica gives the Legislature a final report by early February.

Despite the rosier projections, some lawmakers said at a briefing Monday that they are still grappling with the additional state spending that would be required and the possible effects on businesses.

Richardson would require employers to contribute to a Healthy New Mexico Workforce Fund, offset by whatever they pay for their employees' health benefits.

The proposal is to cap such payments at $500 for each employee, and they could be less, Hyde said.

Without any changes to the health care system, it's projected that about $6.9 billion from federal, state and private sources will be spent in New Mexico in 2010. By the 2014 budget year, that would be $9.2 billion, according to Mathematica.

"Doing nothing is just not an option," said Mary Ruggie, a professor at Harvard University who teaches comparative health policy and outlined for lawmakers what other states are doing.

Unrelated to the computer error, Mathematica also has revised its assessment of what percentage of the New Mexico population under 65 is uninsured. It's now 18 percent, said Deborah Chollet, project director for Mathematica. Previously, the firm had used a figure of 25 percent.

She said updated information from the 2007 budget year that ended June 30 showed a marked increase in the number of people enrolled in Medicaid and other health programs for the low-income, and more residents who had been insured by those programs for more than six months of the year — Mathematica's criterion for being considered insured.

"You're at a better point now than you were a year ago," Chollet told legislators.

The Human Services Department said in a release Monday that August enrollment numbers showed 405,957 people covered by the Medicaid and SCHIP programs, up from 402,018 the previous month. Preliminary figures for September through November show additional increases, said Hyde, who credited her agency's outreach efforts.