A Congressional Business Office analysis that concludes legalizing 2 million "Dreamers" would cost the government $25.9 billion over a decade does not bode well for amnesty programs and contradicts advocates' claims that granting young illegal immigrants amnesty will boost the economy, Jessica Vaughan, director of policy for the Center for Immigration Studies, said Monday.

"When you do the math, it doesn't come out well for amnesty," Vaughan told Fox News' "Fox & Friends," while explaining that the CBO numbers mark a balance between what revenue could be expected and what public assistance and other expenses would be needed to keep Dreamers in the United States.

Friday, the CBO report also once legalized, Dreamers would be able to sponsor another 80,000 people from a process called chain migration, which allows non-nuclear family members to bring relatives into the United States. The Joint Committee on Taxation also has reported that legislation on Dreamers could prove costly.

"This one particular piece of legislation that they analyzed, which was introduced by Sen. Lindsey Graham, [R-S.C.] over the summer would legalize not only the people with DACA [Deferred Action for Childhood Arrivals] but anyone who got here under the age of 18 up to four years ago, so that also includes a large number of the unaccompanied minors who came from Central America as well as the people who got DACA under President [Barack] Obama," said Vaughan.

"It is a much bigger population and younger population. It also doesn't have an upward age cap on it. Lots of older illegal aliens who didn't get DACA would qualify, as well."

The main problem, she added, is that many illegal immigrants are only "lightly educated" and work in unskilled jobs.

"We have gotten the impression that they are mostly college kids, from the activists," said Vaughan, "but the truth is that many of them lack a high school education and are going to acquire access to welfare benefits like healthcare."