Out of 106 apartments, not including ancillary staff units, 82 units, or 77 percent, have recorded sales with the city, said Gabby Warshawer, the director of research at CityRealty, a real estate data firm. Just 12 of those sales were recorded this year, she said. A spokesman for the project said the developer, Macklowe Properties, does not comment on sales.

In spite of the slowdown, other luxury projects have still set audacious sales goals. Central Park Tower, a project under construction at 217 West 57th Street, anticipates sales in excess of $4 billion, according to documents filed with the state attorney general, making it potentially the most expensive residential tower in the city. Sales at that building have not yet been recorded, Ms. Warshawer said.

There are other signs of adjustment taking place. The average time to sell an apartment rose 27.8 percent to 101 days, compared to the same period last year, according to the Elliman report. Buyers also had more leverage, scoring an average listing discount of 5.5 percent, up from 2.9 percent.

“The comment is constantly made that the buyers have left the market. But I think the bigger issue is that the buyers are there, but not willing to pay 2014 pricing,” said Mr. Miller.

If the slowdown in new development is symptomatic of a lull in luxury sales, then the strength of co-op sales may suggest a surge in the entry- and midlevel markets.

“It’s provided a relief valve for people pressed for affordability,” Diane M. Ramirez, the chairman and chief executive of Halstead said about the resilience of co-ops, which tend to be older and less expensive than condos.