[nebula8804]

From Wikipedia:

"The Center for Immigration Studies (CIS) is an anti-immigration think tank. It favors far lower immigration numbers, and produces analyses to further those views. The CIS was founded by historian Otis L. Graham and eugenicist and white nationalist John Tanton."

[1]:https://en.wikipedia.org/wiki/Center_for_Immigration_Studies

Do you have another source? I am not so convinced by this source.

[IncRnd]

There is a section on the methods used, along with naming the dataset, the SIPP.

There is a link to the SIPP in the endnotes of the page. The SIPP is from the Census Bureau.