Passing a bipartisan Obamacare stabilization bill wouldn’t domuch to cushion the blow from repealing the health law’srequirement that all individuals buy health insurance, the Congressional BudgetOffice said.

The CBO has estimated that scrapping the mandate would result in 4 millionpeople losing health coverage in 2019 and premiums in theindividual market to increase by 10 percent. On Wednesday, thenonpartisan Congressional agency said a stabilization proposalbacked by some Republican Senators would have no impact on itscalculations.

The CBO’s conclusion could have an impact on the fate of theSenate tax overhaul bill that is expected toget a vote this week. Senate Republicans included the repeal of theAffordable Care Act’s individual mandate in their tax proposal. Andseveral Senators concerned about their states’ health insurancemarkets, including Susan Collins of Maine and Lisa Murkowski ofAlaska, had pushed forward the stabilization bill as a way tomitigate the blow.

President Donald Trump endorsed the proposal, known as theBipartisan Health Care Stabilization Act, on Tuesday.

“The effects on premiums and the number of people with healthinsurance coverage would be similar to those referenced above,” theCBO said Wednesday.

The CBO projection comes with caveats. It compares the effect ofthe stabilization bill to a baseline in which Obamacare’scost-sharing reduction subsidies are paid. The Trump administrationhas halted the payments, which lower deductibles and out-of-pocketcosts for low-income people, and the funds are the subject of alegal dispute.

“I find it baffling,” Collins said Wednesday. She and Murkowskivoted against earlier Republican efforts to repeal the ACA,blocking them.

The CBO report also doesn’t evaluate the effect of givinginsurers additional funding, an approach that’s also underdiscussion. Collins introduced a bill with Senator Bill Nelson ofFlorida to give states seed money for high-risk pools “which wouldensure that people with pre-existing conditions are protected andalso to lower premiums,” she said on Tuesday. Alexander specifiedthat Collins’s bill would provide $3 billion to $5 billion tostates to set up the high-risk pools. Collins said on Tuesday that Trump also supporters herproposal.

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