Las Vegas- In a slow economy, sex still sells -- but for less.

The Sin City Chamber of Commerce, which built its reputation around events emphasizing cleavage as much as business-card swapping, has seen its membership tumble 17 percent from its peak last year. As a result of even worse numbers earlier this year, chamber leaders rescinded a membership price increase imposed a year ago and have seen a partial member-count rebound, mostly from a higher level of adult businesses than in the past.

"For small businesses with less than five employees, when it comes time to spend marketing dollars the membership fees are the first things to go," said Wayne Bridge, CEO of the 4-year-old Sin City Chamber.

The bulk of those not renewing memberships came from the ranks of so-called mainstream businesses -- the insurance agents, real estate brokers and Web marketers who rubbed elbows with and picked up clients among the Sin City's adult entertainment members. At this point, the share of mainstream businesses has dropped to 68 percent from the 80 to 85 percent quoted in the past, while the adult businesses, ranging from escort services to video producers to sex toy retailers, has risen to 23 percent from the long-standing average of 15 percent.

Bridge attributed much of the change to the decision last July to raise the annual membership for businesses with one to five employees, the large majority, from $400 to $500. In the aftermath, the ranks dropped from a peak of 530 in 2007 to 400 early this year, before Bridge and partner Loretta Holt, Sin City's president, reverted back to the $400 membership fee.

Since then, sales have increased enough to lead him to conclude that only economic woes have hurt the chamber and not a diminished novelty of events such as the annual golf tournament at the Chicken Ranch brothel.

"People still seem to enjoy what we're doing and we're going to keep doing it," Bridge said.

While Holt and Bridge have always touted the chamber's broad base, they acknowledge it would lose a lot of its momentum and purpose without the adult businesses as headliners.

"Everyone has a niche and this is ours," said Holt. If the adult businesses ever decided to leave en masse, she said, "I'd probably follow them wherever they went."

Allstate Insurance agent Dave Sylvester still finds Sin City a good source of policy sales.

"I get a lot of business through referrals from there," he said. "Sin City has a little flair to it and looks a bit spicy to the general public, but I've been able to meet with people in all types of business. They seem to have larger budgets and cash flows" than traditional chamber members.

However, David Jehovek, who advertised his Affordable Flooring in the chamber's welcome map for Las Vegas, is among those who dropped out.

"I have gotten nothing out of it at all," he said. "When you put out money and nothing happens, it gets discouraging."

To diversify the revenue stream of Sin City, a for-profit company, and provide another format for members to promote themselves, Bridge and Holt are putting together a visitors guide that would be a glossy paper counterpart to the chamber's popular Web site.

"When things get tough, you go back to basics," Bridge said.

In addition, Sin City will run the gift shop in the basement of the Erotic Heritage Museum scheduled to open in early August. In late June, Bridge was picking erotic drawings to be silkscreened on T-shirts and deciding on order quantities.

"Sex sells," said Holt. "It's still selling and we want to do what we can to help promote it."