The number of new condominiums put up for sale in the greater Tokyo area surged 77.3 percent in September from a year earlier to 5,968 units, a research institute said Wednesday.

Of the new condos in Tokyo, Chiba, Kanagawa and Saitama prefectures, 83.5 percent found buyers, up 14.2 percentage points from a year earlier and topping 80 percent for the fourth straight month, according to the Real Estate Economic Institute. The average unit price rose 22.4 percent to ¥50.43 million.

The institute said it expects the market will slow in October, with supply staying around 3,500 units.

In Osaka and five nearby prefectures, new condo supply rose 85.3 percent to 3,671 units. The percentage of units sold in the Kinki region came to 80.5 percent.