NEW YORK (StudyFinds.org) — Familiar with your family tree? There’s a good chance you’re not. More than half of Americans don’t know the names of all four of their grandparents.

A recent survey of 2,113 U.S. adults, including 1,911 from the top 10 Nielsen market areas and 202 from Salt Lake City, found that there is a massive knowledge gap when it comes to recent family history. Knowledge of past generations varied by city, as 66 percent of Boston residents could name all of their grandparents, compared to only 26 percent of those in Philadelphia. San Francisco residents weren’t much better at 34 percent, while people in Chicago and Dallas only slightly higher at 36 percent.

As a whole, just 47 percent of respondents could correctly name all four grandparents.

The apple falls a bit far from the family tree

Conducted by OnePoll on behalf of Ancestry, the survey also reveals that only four percent could name all eight of their great-grandparents. When it comes to knowing the most about their family history, three in four people in Salt Lake City say they feel knowledgeable compared to 46 percent of those in Philadelphia.

Despite the knowledge gap, most respondents expressed interest in learning more about their family history (66%). In particular, over half the poll (51%) want to know stories about when their ancestors were young and what their were like at the time.

Most people claim to know the bulk of their family history from parents (43%) or grandparents (40%) relaying stories.

“Listening to family stories is a great starting point to learn about your family’s past, but some details can get lost as they are passed down for generations,” says Crista Cowan, Corporate Genealogist at Ancestry, in a statement. “Digging deeper into records, such as census records, can help fill in the gaps and add rich historical context about more recent family history.”

Catching up with the Census

On April 1, the 1950 U.S. Census was made public. Ancestry is indexing the records state by state to make them searchable for everyone for free. The 151 million newly released records will provide key details about more recent generations.

With the release of the 1950 U.S. Census records, respondents are most interested to learn their ancestors’ employment details, including salary, status and hours worked (38%) and occupations (35%), followed by names (34%) and ages (34%).

“It’s exciting that younger generations now have the opportunity to learn more about family members they know, like parents and grandparents,” Cowan says. “The 1950 Census provides a fascinating look at an era in our collective history, marking the first time baby boomers appear in a U.S. census. The real magic happens when you discover a more complete picture of not only what your family member’s life was like at a moment in time, but also how it had changed over the decades.”