That’s a nice chart. I wonder is it is inversely related to the fertility rate, which was at a high after WWII and is now at an all time low. If you want to stop all immigration, get Americans to start having children again.
No, the rates and numbers of immigrants are dictated by special interest groups. They are not related to job and skill needs. Only 12% of the 1.1 million legal permanent immigrants we take in annually are merit based. Bush 41 signed off on the Immigration Act of 1990 that almost doubled the legal immigration caps.
Check out this short NumbersUSA video