Condominiums put up for sale in greater Tokyo plunged 28.3 percent last year to 43,733 units, the Real Estate Economic Institute said Tuesday.

The year-on-year fall was the sharpest since 1991, when the supply of new condos slid 34.5 percent following the implosion of the stock and real estate bubble, the institute said.

It blamed last year's plunge partly on rising prices, which averaged ¥47.75 million during the year, up 2.8 percent.

The price rise discouraged many would-be buyers, an institute official said.

The higher prices stemmed partly from increased costs for building materials and the rise in crude oil prices that lasted until the middle of the calendar year.

Condo sales "have plunged for three reasons — higher condo prices, falling construction starts stemming from enforcement of the stiffer building standards law and a stricter attitude to lending at financial institutions," the official said.

Many would-be buyers use five times their annual income as a guide when deciding whether to purchase a condo, so the average price in 2008 would have required an annual income of more than ¥9.5 million, leading people to delay buying, the official said.

On average, only 62.7 percent of the condos put up for sale in a given month found buyers by the end of that month.