"Anyone who can do basic math can understand their projections for Obamacare the last time were way, way off the mark," he continued. "I think when they come out with this score, we need to understand their track record when it comes to healthcare."
House Republicans say their new plan will lower health insurance costs and allow patients to have more choices in selecting a doctors. Democrats say millions of people will lose their health insurance, while conservative opponents say the bill is too similar to Obamacare.
A December 2015 report from the Commonwealth Fund, a health policy nonprofit organization, called the CBO estimates "reasonably accurate," adding its predictions were "close to realized experience than we those of many other prominent forecasters."
Still, the analysis, which compared the CBO's 2010 projections with estimates from 2014, said it "overestimated marketplace enrollment by 30 percent and marketplace costs by 28 percent" and "underestimated Medicaid enrollment by about 14 percent."
"If you look at the number of people that they projected would be on Obamacare, they were off by millions," Spicer continued. "The idea that's any kind of authority based on the track record that occurred last time is a little far-fetched."
The March 2010 report from the CBO projected 21 million people would have health insurance coverage via the ACA marketplaces in 2016 and that 30 million fewer people would be uninsured in 2016 as a result of the law.
In the CBO's most recent tally from 2016, it estimates that some 12 million people were enrolled in the marketplaces in any given month in 2016 and that some 22 million fewer people were uninsured as a result of the law.