WASHINGTON (BLOOMBERG) - A total of 144.2 million tax returns with wage income were filed with the Internal Revenue Service in 2016. The data show that the number of returns were split almost equally by gender. But, men earned 61. 4 per cent of total wages.

The data also reveal an interesting dynamic among filers showing US$1 million (S1.37 million) or more in wage income. Among this group, millionaire women out-earned millionaire men. Millionaire women earned US$2,506,220 vs US$2,477,680 for men, on average. Data going back to 2008 show that 2016 was the first time this happened.

The number of female taxpayers with wages of at least US$1 million rose from 6,597 in 2009 - the year the recession ended - to 17,609 in 2016. Aggregated wages for this group of women increased from US$13.8 billion in 2009 to US$44.1 billion in 2016.

Expanding the wealthy cohort to those who make US$500,000 or more show that the number of high earning female taxpayers doubled between 2010 and 2016 to almost 72,000, and they earned close to US$80 billion in aggregate in 2016 or an average of more than US$655,000 each.

While growth among highly compensated women is increasing at a much faster pace, men still hold a large size advantage. Almost 8,000 men earned at least US$5 million in 2016 and more than 400,000 earned half-a-million dollars or more in wage income.

About six times as many men vs women earned an income of US$500,000 or more in 2016 but this is down from 10 times as many in 2009.

The latest IRS data by size of wage income and gender is for 2016.