(From the 2010-2011 final survey done by the American Math. Society, for new Math Ph.D.s, which I linked elsewhere)
Unknown (U.S.): 85
Not seeking employment: 18
Still seeking employment: 53
Unknown (non U.S.): 83
If you count all of these as "unemployed" (which is probably a significant overestimate), that's 239 out of 1653 new Ph.D.'s, or around 14.4%. If you count only "Still seeking employment" as "unemployed", that's around 3.2%. But I don't know how the numbers in the sciences or in engineering would be similar to those in math.
Unknown (U.S.): 85 Not seeking employment: 18 Still seeking employment: 53 Unknown (non U.S.): 83
If you count all of these as "unemployed" (which is probably a significant overestimate), that's 239 out of 1653 new Ph.D.'s, or around 14.4%. If you count only "Still seeking employment" as "unemployed", that's around 3.2%. But I don't know how the numbers in the sciences or in engineering would be similar to those in math.