The argument was that the $7.25 minimum wage in 2009 was already criminally low, and should have been $15. That would be $22.32 now. The actual minimum wage has not been changed since.

The post specifies productivity gains since 1960, though. That's a different measure than inflation, but it's interesting that they arrive in about the same place. There's been a huge gap between average wages and productivity increases over that time period. It's not like the working class was even getting their fair share in 1960, and they sure as hell aren't now.