Here is a lead:

http://www.nilc.org/immlawpolicy/DREAM/DREAM_Demographics.pdf

It is a 2 page report from the Urban Institute that includes the section "undocumented aliens graduating from high school" It appears that the data regarding this subject are estimates only and slightly outdated(2002-3). The estimates I found range from about 50,000-80,000/year.

These are not NYC figures. It is likely that since these are "undocumented" immigrants, a figure is not immediately available.

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