Immigration’s impact on American wages by educational level of workforce

Here are important research data on the impact of how foreign born workers hurt some and help other Americans in wages. Note that these figures pertain only to wage impact. They do not address the lower costs of goods and services and greater corporate productivity which immigration and its companion free trade bring
POORLY EDUCATED WORKERS
Ten percent of U.S. born workers have less than a 12 years’ education. Foreign born workers make up 70% of all workers with less than 9th grade education, and 22% of workers with 8-11 years’ education. In these education categories, foreign born workers MARKEDLY DEPRESS wages by about 4%.
HIGH SCHOOL GRADS and “SOME COLLEGE” EDUCATED WORKERS
Eighty percent of U.S. born workers have between 12 and 16 years’ education. Foreign born workers make up 13% of the HS graduate workforce and 10% of the some college work force. (13% of all workers with HS degree, 10% with some college, and about 15% with college degree.)
For the HS graduate and some college workforces, foreign born workers SLIGHTLY INCREASE wages very slightly, by about 1% – 2%
COLLEGE AND MORE EDUCATED WORKERS
Ten percent of U.S. born workers have masters, professional or doctoral degrees. Foreign born workers make up 15%, 18% and 30% of these workforce categories, respectivelly. These foreign born workers MARGINALLY DEPRESS wages, by about 0.2%.
ILLEGAL IMMIGRANTS
About 4.9% of the American workforce is made up of illegal workers. Few of them have a HS degree or higher education. They GREATLY DEPRESS wages for all workers with less than a HS degree – by 8% — and MARGINALLY INCREASE the wages of the more highly educated workforce – by about 1%.
The data come from Table 5 and Figure 8 of a 2/8/07 presentation by Robert Feenstra of U.C. at Davis. he draws from research by Gianmarco Ottaviano and Giovanni Peri, about whom I have posted.