The number of buyers touring homes and making offers dipped in May and June, according to a new survey by web-centric brokerage Redfin.

The brokerage’s Real-Time Demand Pulse tracks the number of Redfin customers touring homes and making offers in the 20 metropolitan areas across the country where it operates.

The most likely reason for the decrease in demand is a sudden spike in interest rates in June, according to the report.

According to Redfin:

•             The number of customers touring homes fell 1.9 percent from May to June of this year, compared to a 1.5 percent increase between May and June in 2012.

•             Home offers decreased 5 percent from May to June, a slightly larger decline than last year’s 3.2 percent drop.

•             During the last week of June, home tours were down 2.7 percent week over week, compared to a 2.3 percent increase in the last week of June 2012.

•             In the last week of June, home offers increased 1.2 percent week over week, compared to a 2.3 percent week-over-week increase during the same period last year.