Privately owned housing starts took a 12.3 percent dive in June, falling to a seasonally adjusted annual rate of 1.17 million, compared with May’s rate of 1.33 million, according to the U.S. Census Bureau and the U.S. Department of Housing and Urban Development.

The rate is 4.2 percent below the June 2017 housing start rate of 1.22 million.

The National Association of Home Builders blamed the decline on U.S. tariffs recently imposed by the Trump administration upon Canadian construction materials such as steel and lumber.

“We have been warning the administration for months that ongoing increases in lumber prices stemming from both the tariffs and profiteering this year are having a strong impact on builders’ ability to meet growing consumer demand,” NAHB Chairman Randy Noel said in a statement. “This is why we continue to urge senior officials to take leadership and resolve this issue.”

Regionally, the Midwest saw the largest decline in housing starts in June, falling 35.8 percent from May numbers. Starts in the Northeast fell 6.8 percent; fell 9.1 percent in the South; and dropped 3.0 percent in the West.

Building permits in June dropped 2.2 percent compared with May to a rate of 1.27 million. Housing completions remained unchanged at a rate of 1.26 million.