What % of US immigration is of high skilled people?

[rob in cal]

   All the current discussion of immigration reform has got me thinking about the issue of low skilled vs high skilled immigration into the US.  Has anyone done a study of what  % of current legal immigrants would be considered high skilled? What medium skilled? Low skilled? How about current illegal immigration?  My guess is that legal immigration would have a much higher % of high skilled immigrants than illegal. 
    Also, by and large should US immigration policy be for pretty much only, by and large, high skilled people?

[rob in cal]

   Thanks for posting that chart head beagle.  It looks like the type of immigration which is most helpful to the US in terms of the economy, unemployment etc, the high skilled, and investors, is pretty low, and the family reunification part is really big.  Obviously some of that family reunification would be related to those very same investors and high skilled immigrants, but I'm guessing that lots of it isn't.