60 Minutes (7 p.m. Sunday, channels 4 and 12) began the new year happy. Although broadcast viewership is down as a whole, the venerable show’s ratings are up 12 percent to 15 percent over last fall, including two number-one finishes in November — the first time in five years it has been the top-rated show during the regular TV season.

“People are making it appointment television again,” correspondent Scott Pelley said.

So what’s behind this uptick?

Julia Fox, associate professor of telecommunications at Indiana University, theorizes that viewers, inundated with so many news outlets, don’t want to hunt for information. So they’re returning to a show they’ve been able to rely on for 40 years.

“Everyone jokes about how old the personalities are on 60 Minutes,” she said, “but the fact is, they’ve been in the business for many, many years, and they’re very credible.”

Longtime correspondent Lesley Stahl accepts the compliment about credibility and suggests a couple of other reasons for the resurgent ratings: the public’s appetite for news and explanatory journalism, and the timeliness of the show’s stories this season. including the first major interview with President-elect Barack Obama.“We’ve been crashing stories almost every week,” she said (using industry lingo for reporting quickly on timely issues). “We had kind of gotten out of that business — I’m not sure we were ever in it full time — but our feet are really plunged deeply into the idea that we’re covering the big stories of the day this year. No one said, ‘Let’s do that.’ It just happened.”

CBS News president Sean McManus said more viewers are tuning in because 60 Minutes is doing “important stories. It’s not doing pregnant men and it’s not doing prostitutes,” he said. “It’s doing really good reporting. The broadcast is as strong in terms of quality and ratings as it’s been in a decade or so.” McManus credits executive producer Jeff Fager with introducing a contemporary look to 60 Minutes, partly by refreshing the correspondent pool over the past few years — adding Pelley, Anderson Cooper, Lara Logan, Katie Couric and Charlie Rose to join Morley Safer, Steve Kroft, Bob Simon and Stahl — and also by shooting the introductions to the stories in front of a 3-D magazine rather than a piece of cardboardOver the next few months, the show plans to report from Pakistan and Afghanistan. It will have more explanatory pieces on the economy, including a Pelley story in which whistleblowers from the home-loan industry explain predatory lending practices. There will be stories on endangered elephants in Kenya. Violence in Mexico. A profile of actress Kate Winslet. College binge drinking.

“We always think of it as ‘high Murrow’ and ‘low Murrow,’” said Fager, a reference to legendary CBS journalist Edward R. Murrow. The show also tries to stick to creator Don Hewitt’s motto: Tell me a story. Pelley remembers being a 16-year-old in west Texas and writing a fan letter to Hewitt that asked, in essence, “Gee, Mr. Hewitt, how do you do it week after week?”

“This would have been 1974,” said Pelley, who joined the show in 2003. “I got a card from the CBS mailroom saying the letter was received and a reply would be coming. Now, when I see Don in the hallway, I always say, ‘Where the hell’s my letter? You never wrote me back.’ ”

So how does 60 Minutes do it week after week? Pelley has been able to develop his own response: “We go where we have to go, risk what we have to risk and spend what we have to spend to get to the bottom of very important stories.”