This 10-mile strip of beach, boardwalk and buildings, mecca for Washington-area sunseekers and barometer for the tourist trade, today wound up a healthy summer season, the city tourism department reported.

"The economy is improving and people who have deprived themselves of vacations are traveling again," said Susan Seifried, spokeswoman for the department. "A lot of them are choosing to come to Ocean City."

The police who patrol the Chesapeake Bay Bridge said that between Memorial Day and last Friday, nearly 4.5 million vehicles had streamed to the Eastern Shore and back -- about 76,000 more than last summer. And for the Labor Day weekend, between Friday and 11 o'clock tonight,, a tide of 205,482 cars, trucks and vans, most loaded with passengers, had flowed back and forth on the bridge, the police said.

Tourism officials here believe that at least 4 percent more weekend guests showed up this summer than last year -- an estimate the city's ebullient mayor scoffs at as being too conservative.

Mayor Harry Kelley -- whose boosterism is legendary -- pronounces business to be up by at least 6 percent, and says he knows that by using his "peepers" to look at parking lots, vacancy signs and the boardwalk. The tourism department, he said disdainfully, was "using those 'demoflush' figures."

Demoflush is a system, developed by planners in the mid-1970s, to determine the number of people in the city on a given weekend. The numbers are based on the total amount of sewage and waste water generated by bathing and the flushing of toilets.

Gee Williams, who computes the numbers each week for the Eastern Shore Times, says that higher sewage volume means increased visitors. Williams uses information supplied by the Worcester County Sanitation Commission.

"We know it is an accurate barometer," Williams said, "because we talk to a large number of business advertisers and when the demoflush figures go up, they are smiling and happy, and when demoflush dips down they say they've had an off weekend."

At most places along the 30-miles stretch of resorts here at the Maryland and Delaware shore, the story of a strong tourist season was the same.

In Bethany Beach, Del., a small, family-oriented resort whose biggest hotel has 60 rooms, real estate broker Michael Wilgus reported that he had been able to rent just about all the units he could, at a time when a building boom had added about 100 units to his stock of summer housing.

Rehoboth Beach, Del., opened its first tourist information center this summer and did a booming business, said Susan Stone, executive director of the town's Chamber of Commerce.

"People are suddenly coming from all over. We've had visitors from every state except Hawaii this summer," she said.

Most cars spotted cruising Coastal Highway, Ocean City's main drag, today were from from Maryland, Virginia, Delaware and nearby states -- Pennsylvania, New York and New Jersey.

But for George Whyte, 21, the journey here had been much longer. The recent college graduate had traveled from Cork City, Ireland, to work this summer as a bellhop at the Quality Inn, a beach-front hotel at 54th Street.

One of 40 other Irish students and recent graduates who worked in Ocean City this summer, Whyte plans to begin his own vacation next week, after the pace in tourist-packed Ocean City begins to slow. He hopes to travel across the country.

"When we look back at it, I know we'll say, 'Hey, we had very good fun' -- but right now we're working very hard. . . . All holidays mean to us is more work," said a harried Whyte as he jammed suitcases into the trunk of a Mercedes from New Jersey.

While the number of visitors was up in the Ocean City tourism department's count, some restaurant and hotel owners said their business was just keeping pace with last year's, not surpassing it.

Lloyd Byrd, manager of Phillips' Crab House, an Ocean City eatery that often has waiting lines outside, said there was increased competition from new fast-food chains and and more expensive restaurants this year. "That's the bottom line," Byrd said. "The number of new places on the beach each year is just staggering."

The number of licensed businesses in town has increased from about 2,200 last summer to about 2,400 this year, Gary Fisher, the city's director of tourism, said.

Fisher said that spending throughout the city, where tourism is a $650-million-a-year enterprise, is running about 4 percent higher than last summer. But some businesses might not be cashing in on that, he added.

During poor economic times, such as last summer, Ocean City gets the "high spenders," who buy more and are willing to pay top dollar, Fisher said. When times are better, as they have been this summer, these people take more exotic vacations, he said. The tourists who do come to Ocean City don't have as much disposable income, and therefore spend less per person, Fisher said.

And, despite the generally bright picture this summer, patches of cool, rainy weather in the mid-Atlantic region cut into some resort business, said Hale Harrison, who owns six hotels and five restaurants in Ocean City.

"We have an old saying in the business that we like it to get so hot that your shoes stick to the macadam on the sidewalk," noted Harrison, who said stretches of very hot weather in the metropolitan areas often send tourists scurrying to the shore.

"We're talking about the impulse travelers," people who make a last-minute decision to head for the beach, Harrison said. "That is a very important part of our market in Ocean City."

Impulse travelers were slim on luck this weekend because most hotel rooms had been booked weeks and even months in advance, a spot survey among reservations clerks indicated.

And as for the "demoflush" figures for summer's traditional last weekend, they weren't available today: Like workers across the county, the man who computes the numbers and employes of the sanitation commission had the day off.