A build-up of industry income changes could have driven the pay gap between men and women to a historic low

The pay gap for the June quarter's sitting at 5.2 percent - down from the 8.2 percent seen a year ago.

It's the smallest margin seen since Stats NZ began collecting the data in 1998.

Infometrics principal economist Brad Olsen says sectors like transport, IT and finance have been pushing through higher incomes for female workers.

He says there've also been continued large pay increases for more female-dominated industries like education and health.