Why are we still making buildings without a 13th floor?

If you got on a plane Friday morning, or traded a stock, or drove your car through an intersection, congratulations. You're too logical for medieval superstitions.

And if you worked from home - under the covers after e-mailing the office "WFH/Friday the 13th"?

Congratulations again - you're in the good company of New York's boldest real estate developers. Twelve centuries after the Omens of Charlemagne's Death, they are still labeling the floor that comes after 12 as 14.

Fewer than 10 percent of Manhattan condominiums with 13 or more stories label a floor with the dreaded number, said Gabby Warshawer, director of research at data and listings company CityRealty. That estimate is based on 650 mid- and high-rise buildings that have filed condo declarations with New York City since 2003.

A spokesman for Otis International, the elevator maker, once estimated that 85 percent of U.S. buildings with more than 13 floors skipped the unlucky number. Otis' current press office could not confirm that statistic.

(Philadelphia's tallest building, the Comcast Center, is more commercial than residential, but it bucks the trend. It has a 13th floor.)

New York builders seem to be getting more superstitious, not less. Newer buildings seem even likelier to skip 13 than older ones, Warshawer said. But why are the titans who borrow scary sums to erect towers that defy gravity afraid to number the 13th floor? "Marketing people want to appeal to the largest audience," said Jacqueline Urgo, president of the Marketing Directors, a New York real estate consultancy that helps developers made these kinds of decisions.

Here's another theory: Pulling a number - or many of them - out of the floor plan only serves to make a building seem taller. Apartments on higher floor numbers command higher prices, said Jonathan Miller, chief executive of appraisal firm Miller Samuel. "From a marketing standpoint, it's pretty powerful," he said. "The taller you get, the thinner the competition is. If you're on the 90th floor, there are only a handful units."