Purchases and prices of previously owned homes on Oahu slid in July, according to a report released today by the Honolulu Board of Realtors.

The decline for single-family home sales was 7 percent to 251 transactions last month, down from 270 a year earlier. The median price slipped 2.2 percent to $591,000 from $604,500 in the same period.

July was the fourth consecutive month that single-family home sales have been lower than the same month last year. The median price has been down in six of the first seven months of this year.

In Oahu’s condominium market, the number of sales was down 8.3 percent to 300 in July from 327 a year earlier. The median price was down 7.7 percent to $277,000 from $300,000.

Condo sales have been down for five consecutive months this year, while the median price has been down in four of the first seven months of this year. However, the July decline was the largest this year, and pushed the median price down to its lowest level in roughly six years. The last time Oahu’s median condo sale price was lower was July 2005 at $270,000.