(CN) – The percentage of U.S. adults who are married has fallen steadily over the past 40 years, but married people continue to earn more than their unmarried colleagues and pay the vast majority of income taxes, the Pew Research Center said Thursday.
Pew researchers analyzed IRS tax administration data and found that in 1970, 69 percent of adults in the U.S. were married and they paid 80 percent of all federal income taxes.
As of 2014, the most recent year that complete tax data are available, the share of married adults dropped to half the population — 50 percent — but the share of income taxes paid by them fell much less, to 74 percent.
The same period saw a sharper decline in the share of all tax returns filed as married (either “married, filing jointly” or “married, filing separately”), the Pew Center said.
In 1970, married returns accounted for 60 percent of all returns, but fell to just 38 percent in 2014.
The Pew Research Center said the fact married Americans continue to pay roughly three-quarters of the nation’s income taxes, in spite of their dwindling share of the adult population, is in part a result of the changing demographics and economics of marriage.
Marriage is increasingly linked with higher levels of education, which are in turn linked to higher incomes, the organizations researchers said.
This marriage and education gap has widened as the share of high school graduates who are married has fallen more sharply than the share of college graduates who are married.
In 2015, 45 percent of adults ages 18 and older with a high school degree but no college experience were married. This compares with 62 percent among those with a bachelor’s degree or higher.
In 2014, the Pew Research Center said, the average return filed by a married couple or individual reflected an adjusted gross income that was more than three times that of the average unmarried return –$115,100 compared with $35,200 – a gap that can be partially explained by the fact that many married returns are filed by two-income households.
The analysis also found that married filers are more likely than unmarried filers to pay federal taxes.
In 2014, 76 percent of married filers owed some tax, and among those who paid taxes, the average tax rate was 16 percent.
By contrast, 58 percent of unmarried filers paid at least some income tax in 2014, at an average rate of 13 percent, the center said.