The most recent data I have been able to find was the decade 1997-2007
http://www.industryweek.com/articles...ing_14159.aspx

The first thing that you will notice is that manufacturing employment decreased from 17 to 14 mullion during that period - a loss of 3 million jobs. This brought manufacturing employment below 16 million for the first time in decade. The unemployment is primarily created by productivity improvements. As the article points out manufacturing productivity increased by 94% in the twenty year period between 1981 and 2001. For this to happen with employment remaining constant, means that twice as much is being produced with no increase in the number of workers.

American workers are the most productive in the world, largely because we have increased output through capital investment. This has been the pattern since 1900. At that time over 90% of the population lived on the farm and produced food for the less than ten percent to consume. Today, the farm population is less than five percent of the total population and they produce not only enough food to feed us all, but enough to export billions of dollars worth of food. This means the farm output per person has increased productivity by more 20 times during that period. We did not lose farm jobs because of overseas producers undercutting US prices, but rather by the increase of farm productivity.

We need to shift to an economy that is largely service and information based as manufacturing jobs decrease just as manufacturing output is increasing.