Most of the increase in wages has gone to what group of people?

I would say that unionized workers are the ones who have been the most successful at obtaining increases in wages because they are united in a common goal with a recognized defence organization with the power to stop work or file grievances if their demands are not met. They have strength in numbers and in being the main producers of the wealth. Those on staff often benefit from their wage struggles and get a raise when the hourly workers get a raise too.