Just a reminder, your average factory worker today can buy a pound of butter with only 20 minutes of labor, compared to only 100 years ago and that same amount of food would have taken 3 hours of labor to earn.
@freemo That would be my hypothesis. Though I am frequently wrong. ;-)
My understanding is that the gains you speak of were largely won by organised labour. Deregulation of markets and weakening of trade unions since the 80s has demonstrably led to wider inequalities between workers and executives, which would suggest the gains in worker buying power should at the very least have slowed since then and possibly gone backwards.
@VoxDei you are expecting the 1975 numbers to be significantly better than current numbers and 1900 numbers I take it?