Washington ? Nearly half of American dads under 45 this Father’s Day say they have at least one kid who was born out of wedlock. And the share of fathers living apart from children is more than double what it was not so long ago.

In encouraging news, though, among married fathers, children are said to be getting more attention from both parents at home than ever before.

A Pew Research Center report highlights the changing roles of parents as U.S. marriage rates and traditional family households fall to historic lows.

For example, college-educated men who tend to marry and get better jobs are more involved with their children than lesser-skilled men struggling to get by.

“When a father can’t provide monetarily for his offspring, he often becomes estranged,” said Beth Latshaw, an assistant sociology professor at Appalachian State University, who researches changing paternal roles. She pointed to an economic advantage for college graduates hired at companies with better benefits and family-friendly policies, contrasted with the situation for the larger ranks of low-wage workers.

“As a result, many women now raise children outside of marriage or without a father figure,” Latshaw said.

Pew’s survey and analysis of government data, released Wednesday, found that more than one in four fathers — or 27 percent — with kids 18 or younger live away from at least one of their children. That number is more than double the share of fathers who lived apart from their kids in 1960.

On the other hand, married fathers who live with their children are devoting more time helping their wives with caregiving at home, a task once seen almost exclusively as a woman’s duty. Such fathers on average now spend about 6.5 hours a week on child care, which include playing, helping kids with homework or taking them to activities. That’s up from 2.6 hours in the 1960s.

The 6.5 hours is still just half the amount of time mothers spend per week. Still, it is a gap that is narrowing; in the 1960s, fathers put in one-fourth the time mothers did.

“Father’s Day reminds us parents that we have no more solemn obligation than to care for our children. But far too many young people in America grow up without their dads, and our families and communities are challenged as a result,” President Barack Obama said Wednesday in calling for fathers to be more involved. Next Sunday is Father’s Day.

Obama has often reminded Americans how his father left his family when the future president was a small child, describing a “hole in a child’s life that no government can fill.” The Health and Human Services Department in conjunction with the Ad Council is now running public service advertisements this week urging fathers to “Take Time to Be a Dad Today,” and the administration next week is expected to announce new support for local fatherhood programs.

The ads this year focus on Hispanic fathers and military dads sharing small moments with their children.

The Pew study, entitled “A Tale of Two Fathers,” found sharp differences based on race and education. Black and Hispanic fathers were much more likely to have children out of wedlock, at 72 percent and 59 percent, respectively, compared to 37 percent for white men. Among fathers with at least a bachelor’s degree, only 13 percent had children outside marriage, compared to 51 percent of those with high school diplomas and 65 percent of those who didn’t finish high school.