But after two weeks of disappointing apartment sales, it was converted again - this time into an office complex.

One factor behind the trend is that building residents often have the inside track on apartment sales.

Although hundreds of apartment sales are recorded by the city each week throughout the summer, an increase in activity was reported in recent weeks.

The city would also receive 20 percent of the gross revenue from rentals, fees and potential apartment sales at the site.

Cash from apartment sales, about $2,500 a unit, was to help pay off some of the building's loans.

Total apartment sales so far, she said, add up to $810 million.

Statistics on apartment sales are only available back to 1999, but that is the worst showing in that period.

There have been no apartment sales for over one year.

A new study of a decade of apartment sales illustrates this trend.

In recent years, the total number of annual apartment sales in Manhattan has been estimated at 10,000 to 12,000.