New York City fathers make more money than their male counterparts who don't have children, according to a new study. Additionally, fathers earn more than New York City women, whether they have children or not. 

The findings come from a recent study by the City University of New York. CUNY Ph.D. candidate Justine Calcagno used American Community Survey data, released by the U.S. Census Bureau, to analyze New Yorkers' personal incomes in 1990 and 2010.

In 1990, the median personal income for men with children was $28,302. They beat out men with no children--who earned a median salary of $19,224. And fathers earned more than double the earnings of both categories of women--those with children and without children--who earned a median salary of $12,816 and $13,884 respectively.

Flash forward two decades later, and the comparisons look similar. In 2010, men with children earned a median income of $40,947, and those without earned $29,904. Mothers earned a median income of $24,350, and those who didn't have children earned $24,244. The findings were consistent across occupations, different levels of education and race and ethnic groups, the report said. 

Without a doubt, there are a number of factors behind these figures. Several readers commenting on a Wall Street Journal article suggested that when men become fathers, particularly if they are the household breadwinners, they will work harder and put in longer hours to support the family. However this can't be concluded from the study, as it didn't look at hours worked per week. 

On the other hand, women have been more likely than men to take up to several years off to run the household, resulting in a loss of years of experience that could bump up their earnings. 

Calcagno suggested that there could be psychological factors at work, on the part of the employer, that cause fathers to get ahead financially.

"There are some social psychologists who [describe] certain stereotypes about men with children -- that they’re more warm, that they’re more devoted --  all these sort of positive factors we attribute to dads," Calcagno told WSJ. "That may be one reason why employers are biasing in terms of their pay."

Calcagno said her next step is to expand the study to include national data.