Stars of the "Harry Potter" films — in back, from left, Emma Watson, Rupert Grint and Daniel Radcliffe — have grown up since the first film in 2001. As they age, so do the audiences going to see their movies. Many of them are of Generation Y: They were born between 1980 and 2003.

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'Harry Potter' inspires Gen Y's nostalgia

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As anyone who has seen the box office phenomenon "Harry Potter and the Half-Blood Prince" surely noticed, the movie's main characters have grown up. And so has its audience: Many of those who are streaming to theaters are in their 20s.

The sixth film in the series was released almost a dozen years after the book that started it all: "Harry Potter and the Sorcerer's Stone."

The generation that ignited Pottermania as preadolescent readers is approaching college graduation or entering the workplace, and they have kept alive this flame of their early adolescence.

The continuing pull of all things Potter is a testament to the franchise's enduring sway. But it also seems like something else: the advent of Generation Y nostalgia.

"I associate 'Harry Potter' with my childhood," said Becca Cadoff, 21, a senior at Northwestern. "I couldn't wait for the books to come out. We went to midnight parties at our bookstore in New Jersey."

Now, she said, her roommates have all the Potter films on DVD. "It's a release from all the schoolwork," she said.

According to a survey of 4,000 people who bought tickets to the new "Potter" movie through Fandango, the online ticket service, 45 percent were 18 to 30 years old, compared with 15 percent under 17.

Let the boomers have their 40th anniversary of Woodstock. Let Generation X commemorate the 15 years since Kurt Cobain shot himself. For Generation Y — those born roughly between 1980 and 2003 — it's the pop culture of the late '90s and early 2000s that makes them wistful.

Pop music is cashing in this summer on the first glimmers of the trend. Acts that dominated the charts a decade ago but then disappeared are back. Eminem's comeback album, "Relapse," has sold 1.2 million copies (an impressive figure in today's anemic music business), while three of the biggest bands of the period — Blink-182, Limp Bizkit and Creed — have each reunited for summer tours.

Seth Matlins, chief marketing executive at Live Nation, the concert promoters, refers to those acts as "classic rock for the next generation."

The top-grossing tour of the year so far is not Bruce Springsteen or AC/DC, but the Gen-Y icon Britney Spears.

"It could be her original fans coming back for a nostalgic return," said Gary Bongiovanni of Pollstar, which tracks concert sales. "It's like the New Kids on the Block tour, which drew women in their late 20s revisiting their youth."

Just as it has been throughout their lives, the demographic clout of Gen Y (now ages 6 to 28) has strong appeal to marketers.

"Twenty to 30-year-olds are the epicenter" of the concert industry, Matlins said.

Even though nostalgia hits every generation, it seems awfully early for 28-year-olds to be looking back. One possible explanation, say authors who focus on generational identity, is the impact of the terror attacks of Sept. 11, 2001. The political and economic climate of the late '90s had been as soothing as a Backstreet Boys ballad: no wars, unemployment as low as 4 percent, a $120 billion federal surplus.

Neil Howe, an author of several books on what he calls the Millennials (another term for Gen Y), draws a parallel between this nostalgic wave and the one boomers embraced with the film "American Graffiti" in 1973. That movie depicted the recent past, the early '60s, which seemed to have vanished forever.

"It's instant nostalgia before a huge change in the nation's mood," Howe said. " 'American Graffiti' was nostalgia for the boomers for a world before everything changed after JFK's assassination.

"Millennials see the world before Sept. 11 as a period of innocence. Our biggest worry was the Y2K bug. That all seems a world away now."

While boomers or Gen Xers might have no idea what the phrase "classic Nickelodeon" implies, to anyone in his or her 20s, it means fondly remembered cable tween shows like "All That" and "Clarissa Explains It All."

Aaron Eisenberg, a 20-year-old theater major at Northwestern, fondly recalled his Austin Powers Halloween costume, the day he bought the Backstreet Boys' "Millennium" album, and how much funnier Adam Sandler was when he blew off steam in films like "Happy Gilmore" and "The Waterboy."

And don't even bring up Blu-ray. "I miss VHS tapes," he said. "I can't find a way to watch any of my Power Rangers videos."