CEOs are using one number in the AI age to decide how many people they still need

Tim Walsh knows the the metric that is quietly reshaping how corporate America thinks about its workforce. It isn’t revenue per employee, which has anchored headcount decisions for decades. It isn’t productivity. It’s something Walsh, the chair CEO of KPMG U.S., calls labor cost margin — and understanding it reveals more about where AI is actually taking the economy than almost anything else being said out loud in boardrooms right now.

“For every one of my engagements,” Walsh told Fortune, the question is “what is my mix of labor?