(John runs out from under the porch with the dreaded soap box in hand!)

When I was younger, four-by lumber was missing 1/4 in thickness.  Then, another
1/8 disappeared. In recent years it's been missing a full 1/2".
 
Whose idea was it that construction lumber should be surfaced on four sides?! 

I grew up in a circa 1900 house where the rough-sawn studs were fully 2x4 after
70 years of drying.

Less is not more! 

Think of this in Board Feet!!! 

 Fair standards are not generated by trade associations!  Throughout history,
human nature has necessitated that weights and measures be dictated by fiat and
checked at frequent intervals for cheating.

How do metric countries handle this?

John Ruth