[gubamyster]

A good many of these illegals are probably busting ass and producing.

From the study:

Tired & Poor: Bankrupt Arguments for Mass, Unskilled Immigration

We at the Center for Immigration Studies estimate that the average Mexican immigrant will use $55,200 more in public services during his lifetime than he pays in taxes. In effect, Mexican immigration acts as a subsidy to businesses that employ unskilled workers, holding down labor costs while taxpayers pick up the tab for providing services to a much larger poor population. It's like any other subsidy: Businesses that receive it want it to continue, but for the nation as a whole, it's a bad deal.

More like, one or two living in the house will be paid under the table and be able to pay the mortgage for the other 10 - 15 living in the same house. All the while, the taxpaying citizens will pay for their social services.

[Fester Chugabrew]

I hear ya. Don't know whether to trust those figures, but I hear ya.

[Alberta's Child]

We at the Center for Immigration Studies estimate that the average Mexican immigrant will use $55,200 more in public services during his lifetime than he pays in taxes.

I don't question this number, but I strongly suspect that this is more a function of the business sectors in which Mexican immigrants tend to work than anything else. I'll bet the differential between services received and taxes paid for the average all-American, heartland-type grain farmer is about ten times the value you see posted here for Mexican immigrants.