U.S. lumber futures tumbled from a record high for the sixth straight session, pushing some builders to the sidelines while they wait for even lower prices during North America’s boom in home construction.

The price of lumber for July delivery has dropped 23% from its May 10 peak of $1,733.50 per 1,000 board feet -- a level then that was more than four times higher than a year ago. Prices have fallen for six straight days, marking the longest streak for declines since September.