Lawmakers on Capitol Hill have only a short window of time to vote on the latest Republican legislation to gut and replace the Affordable Care Act, and if the GOP is going to push forward with a vote on this bill they will likely have to do so without having an idea of how many Americans will be affected, or what impact it might have on insurance rates.

The nonpartisan Congressional Budget Office is currently attempting to put together a score for the so-called “Graham-Cassidy” bill in the Senate. CBO scores on previous repeal bills provided legislators and the public with estimates on how the proposals would affect the number of uninsured Americans, insurance premiums and other costs, and the overall effect on the federal budget.

However, last night the CBO announced that while it intends to get an initial report out early next week on the Graham-Cassidy bill, that first score will contain very little information, beyond some very specific data about the bill’s potential impact on the deficit.

For projections on how Graham-Cassidy could affect insurance coverage and premiums, the CBO says it will need “at least several weeks.”

And there’s the rub. Aside from a general eagerness among some Republicans to pass some sort of repeal bill this year, the GOP has a relatively narrow window of time to realistically reach that goal.

As with the previous House and Senate repeal bills, Graham-Cassidy is not a traditional piece of legislation. Rather, it is a budget resolution. While there are all manner of rules associated with passing a budget resolution, the two that are most important here are the number of votes needed and the deadline for passing.

A traditional bill needs at least 60 votes in the Senate to avoid dying in a filibuster; a budget resolution only needs a simple majority. In fact, because any tie in the Senate is broken by the Vice President, the GOP would only need to get to 50 votes (and possibly 49, if Sen. Bob Menendez of New Jersey is unable to vote because of his ongoing trial). This is important because the GOP only holds a 52-48 majority in the Senate; since Republicans can’t realistically hope for 60 votes on a repeal bill, they need to pass Graham-Cassidy as a budget resolution.

But, they also need to pass it this month. Sept. 30 is the deadline for the Senate to pass budget resolutions. If they don’t pass the bill by that date, then they would have to wait until the next budget window opens in 2018.

Unless the CBO is being overly cautious about needing “at least several weeks” to fully score Graham-Cassidy, it seems highly likely that any Senate vote would be made without the benefit of essential information about the potential impact of this bill.

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