At a seasonally adjusted annual rate of $650.5 billion, new construction starts in November dropped 12 percent from October, according to Dodge Data & Analytics.

Nonresidential building fell 14 percent in November, retreating for the second month in a row after the sharp improvement reported in late summer. The nonbuilding construction sector, which can be volatile on a month-to-month basis, plunged 32 percent in November after its 28-percent hike in October, which included the start of two large natural gas pipeline projects.

November’s data lowered the Dodge Index to 138 (2000=100), down from 157 for October and this year’s high of 173 for September, which reflected the boost coming from several unusually large projects.

“While total construction starts fell considerably during October and November, the declines came after an exceptionally strong September,” says Robert Murray, chief economist for Dodge Data & Analytics. “If one takes the average of September, October and November, total construction starts during that period would be down only 1 percent from the average of the previous eight months. On balance, the construction expansion has continued during 2017, although it’s true that the rate of growth has slowed from the 6-percent gain reported for 2016 as well as the 11-percent to 13-percent yearly gains reported from 2012 through 2015.”