SALEM — Gov. Kate Brown says nearly half a million Oregonians may lose health insurance through 2026 under the federal health care overhaul proposal, potentially tripling the rate of uninsured individuals to 15 percent as older adults could see premiums jump fivefold and roughly 23,000 health workers may lose their jobs.

Brown and state health officials said Thursday federal changes under the American Health Care Act would begin next year with an estimated 80,000 people on individual and group plans losing eligibility for coverage.

The data came from a 19-page report compiled by the Oregon Health Authority and the Consumer and Business Services Department per Brown's request in response to last week's introduction of the AHCA on Capitol Hill.

"For every step of progress that Oregon has made, this proposal will take Oregon three steps back," Brown said during a press conference Thursday. "This bill is not about improving health care. It's about giving tax cuts to the wealthy."

The most potentially significant impacts wouldn't kick in until 2020 when the phase-out of federal funding begins for the 375,000 low-income and disadvantaged Oregonians currently covered under the Medicaid expansion — almost 40 percent of all Medicaid enrollees in Oregon and by far the biggest chunk of the estimated 465,000 coverage losses statewide over the next several years.

Oregon is already facing a $1.6 billion-hole in its upcoming 2017-19 budget, mostly from public pension costs and cuts to federal Medicaid dollars that pre-date the new White House administration. Likely prolonging the state's budget woes is the current GOP proposal to phase out Medicaid expansion and cap that program for the future. Under that scenario, 375,000 Medicaid enrollees in Oregon would either lose eligibility between 2020 and 2023, or the state would have to find an additional $2.6 billion to cover the federal government's share.

According to Oregon Health Authority statistics, 63,453 Jackson County residents are on the Oregon Health Plan, or 30.1 percent of the county's population. The number of Jackson County residents receiving OHP benefits because of expanded coverage under the 2010 Affordable Care Act is 25,173, or 12 percent of residents. Oregonians who receive federal subsidies to buy private insurance through the Oregon Marketplace get an average subsidy of $349 per month. The average monthly subsidy for Jackson County residents is $432, according to OHA.

Nationwide, 14 million people would lose coverage next year under the House bill dismantling former President Barack Obama's Affordable Care Act, according to the Congressional Budget Office's latest estimates disclosed Monday. Under the estimate, there would be 24 million more people uninsured by 2026 than under current law.

The GOP legislation would eliminate the current mandate that nearly all people in the United States carry insurance or face fines, would use tax credits to help consumers buy health coverage and expand health savings accounts. It would also repeal several taxes and end some requirements for health plans under Obama's law.

Diane Goodmanson, 58, a Salem chiropractor and yoga teacher, says she almost lost her ability to walk because a preexisting condition had locked her out of the insurance market. An MRI through her Obamacare insurance later revealed she had advanced degenerative arthritis in both hips.

"The Affordable Care Act literally gave me my life and career back," she said Thursday. "Without it, I likely would not be working or walking. I would've probably lost my business and home."