WASHINGTON (AP) — American factories grew last month at the slowest pace in more than two years.

The Institute for Supply Management, an association of purchasing managers, says its manufacturing index dropped to 54.1 in December, down from 59.3 in November and lowest since November 2016. Anything above 50 signals growth, and American manufacturing has been on a 28-month winning streak.

Still, the December drop was bigger than economists had expected.

New orders, production and factory hiring all grew at a slower pace last month. Eleven of 18 manufacturing industries reported growth last month, led by textile mills and apparel makers.

Several respondents cited higher costs and uncertainty arising from President Donald Trump's import taxes on steel, aluminum and hundreds of Chinese products.