WASHINGTON (AP) — Fewer Americans signed contracts on homes in April compared with the prior month, potentially signaling that rising prices have outweighed recent declines in mortgage rates.

The National Association of Realtors said Thursday that its pending home sales index fell 1.5% to a reading of 104.3. Pending sales declined 2% over the past year.

Sales have been hampered even with average 30-year mortgage rates slipping below 4% this week, according to mortgage buyer Freddie Mac. That average is down from nearly 5% in November, though cheaper home loans have done little to boost real estate purchases. Home prices have risen faster than incomes in 78% of U.S. areas since 2012.

Pending sales is a measure of home purchases that are usually completed a month or two later.