This is not a perfect exercise.
The value of the federal minimum wage in 1968 was $1.60 according to
http://www.dol.gov/whd/minwage/chart.htm
and using the inflation calculator at
http://data.bls.gov/cgi-bin/cpicalc.pl?cost1=1.60&year1=1968&year2=2012
gives us a value of $10.50 in 2012 but the actual minimum wage is only $7.25. This is a loss of $3.25 per hour or $6,760 a year for a full time MW worker.
According to http://www.bls.gov/cps/minwage2012tbls.htm some 3.55 million wage workers got this minimum wage or below in 2012
3,550,000
6,760 ×
--------------------------
$23.998 BILLION = lost wages
This number only includes those at the minimum wage or below... NOT those between the minimum wage and the $10.50 per hour range.
So who's benefited from this $24 billion a year subsidy the economy got in 2012? And remember these are just rough numbers for one year.
This raises other issues of increased safety net expenditures AND
lost tax revenue. But then we can always kick the can down the road by
borrowing for those safety net programs so future taxpayers will be
subsidizing our irresponsibility today.
ulTRAX