It shouldn’t come as a surprise if Members appear to be sporting more bald pates and silver hairs these days: A new database launched this week proclaims the 108th Congress the oldest in history.

According to the firm that assembled the rankings, the current House and Senate is the most advanced in age, with Senators boasting an average age of 60, while Representatives clock in at 55.

More strikingly, the analysis found that “Generation X” — those individuals born between 1961 and 1981 — is the slowest in U.S. history to attain political power.

Overall, Generation X held just 5 percent of national leadership posts, defined as the average of each generation’s share of House seats, Senate seats and state governorships.

By contrast, the year the first baby boomers turned 42 — the age the researchers used to compare generations across time — they held a 13 percent share of that leadership pie. Boomers currently fill a majority of House seats and a plurality of Senate seats.

It’s a finding that may have implications for everything from partisanship levels to the policy focus of Congress.

“The longer boomers are in power, the longer the culture wars go on. Xers are more pragmatic,” said Mike Weber of LifeCourse Associates, which put together the database. “I don’t think you’ll ever see Xers shut down the government or impeach the president. Also, I think Xers will be fiscal realists.”

LifeCourse Associates is headed by Neil Howe and William Strauss — two authors and commentators who coined the term “Millennial Generation,” which refers to those born roughly between 1982 and 2002. They were also crucial in the initial public discussions defining Generation X.

Outside experts say there may be something to the LifeCourse analysis.

For instance, the older the Congress, the more emphasis on issues such as Medicare, prescription drugs and Social Security, said presidential historian Allan Lichtman.

Lichtman also suggested a theory on why Generation Xers have come to power relatively late.

“They didn’t have that great defining moment,” said Lichtman, contrasting the searing impact of the Depression, World War II and the Vietnam War on previous generations.

What’s more, societal expectations have shifted noticeably, with Generation Xers benefiting from a more diverse array of professional options beyond electoral politics.

Michael Barone, co-author of “The Almanac of American Politics,” said he doesn’t detect as “many self-starting political entrepreneurs in this generation [as] you did in the previous one.”

While cautioning that such trends may not explain everything, Kenneth Kato, chief of the House’s Office of History and Preservation, agreed that “career ladders change over time.” Since the educated class “now can do anything they want” — from the creative arts to entertainment to business — “it’s not surprising that you are going to see fewer people going into public service.”

In addition to analyzing the demographics of Congress, the database — www.lifecourse.com/leaders — also contains average ages and generational data on state governorships, the Supreme Court, presidents and vice presidents. The group used figures in the “Biographical Directory of the U.S. Congress, 1774-Present,” averaging the age of all individuals serving in a given Congress over the two-year period, using the age a Member turned during the first year of that Congress. Ages were then rounded up to the nearest whole number.

Some of Congress’ youngest Members, such as Rep. Devin Nunes (R-Calif.), pointed to advances in health care and rising life expectancies as likely causes of an older Congress. But others, such as Rep. Adam Putnam (R-Fla.), refused to accept the study’s premise. “It’s a statistical anomaly,” he said, reeling off a list of Congressional youngsters, including himself, Nunes, Reps. Harold Ford Jr. (D-Tenn.) and Tim Ryan (D-Ohio).

For his part, the dean of the House, Rep. John Dingell (D-Mich.), barely flinched when informed of the news. “We’re doing what we can to get them involved,” he said of younger Americans.

Senate and House officials said the advanced age of Congress did not in itself hold much significance for the institution. After all, they noted, the average age of the preceding Congress, according to the LifeCourse analysis, was only one year less in both the House and Senate.

For the most part, “since 1885 the average [of the Senate] has been over 55,” said Senate Historian Richard Baker. From time to time, he said, there are “large turnovers in the Senate” that could affect both the average age and the generational hold on power. For instance, during the three elections from 1976 to 1980, 55 new Senators were elected, he said. Although recent years have seen three Senators break the 40-year service mark, Baker said, given the small number of Senators, the institution “is not very reliable statistically.”

In the House — where redistricting has sharply reduced the number of competitive seats — tenures are on the rise, which could also partly explain the aging membership, said Kato.

While the database does not address the rates at which Generation Xers have sought office, Weber — who self-published a book for state legislators on American political leadership through the generations — said that his anecdotal research points to “skeletons in the closet” as a key determinant in convincing Xers to forgo runs for office.

“They are concerned about things they did in college — drugs, sex,” he said.

Weber added that once more Generation X women have finished raising children, he expects to see a spike in the number of Xers holding office. Currently, only four of 47 Generation Xers in Congress are women.

Despite being slow out of the gate, Xers are expected to seize power eventually, in what could become a dramatic power shift. But Howe warns that they ought to watch their back.

The Millennial Generation is set to be “a political powerhouse,” said Howe, pointing to that generation’s more community-oriented upbringing and team approaches to problem solving, as well as the service-inspiring effects of the terrorist attacks of Sept. 11, 2001. The oldest Millennials are roughly college age.

“With the Millennial Generation now on campus, we are going to see even in this coming election … the first signs of a complete reversal in the apathy and withdrawal we have seen among Generation X,” he said.