This is the answer I intended to write. It's a mistake to tie to another abstract metric, like "what was it in 19XX, raised for inflation."

The only exception I'd make are for nonprofit businesses, which you could build into the equation anyway, and some exception/grace period for unprofitable businesses since there are variations in profitability (I'd even be ok with government subsidies to fill in the wage difference if the business has community value).

Essentially, if a business is making profit, the "cream" skimmed off the top after refilling the "costs" jar, that is in no uncertain terms the excess life value being taken from the workers. If the CEO, shareholders and C-suite are going to take that, I actually don't have a problem with them making more money or having a better share of profit, but every person working there should have a livable wage first. That said, yes, I think executive pay should be a multiple of the lowest-paid worker.