The U.S. Chemical Production Regional Index (U.S. CPRI), which tracks chemical production activity in seven regions of the United States, dropped by 0.4% in September, following a revised 0.2% decline in August, according to the American Chemistry Council (ACC).

On a three-month moving average (3MMA), output of the nation’s overall manufacturing sector edged higher by 0.1% in September, after increasing 0.2% in August. Within the manufacturing sector, output in several key chemistry end-use markets grew, including motor vehicles, construction materials, machinery, fabricated metal products, semiconductors, plastic and rubber products, structural panels, textiles, and furniture. Manufacturing continues to expand following weakness during the second quarter. Stronger growth abroad, in addition to accelerating demand for autos, aerospace and construction are key drivers, ACC said.

Also measured on a 3MMA basis, overall chemical production was again mixed. Gains in the output of organic chemicals, synthetic rubber, manmade fibers, adhesives, and fertilizers, were offset by lower production of inorganic chemicals, pharmaceuticals, acids, consumer products and plastic resins.

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Compared to September 2012, total chemical production in all regions decelerated to a 1.4% year-over-year gain, following a 1.8% gain in August. Chemical production remained ahead in all regions compared to a year ago. Comparing the first three quarters of 2013 to that in 2012, chemical production was up 1.1% nationally, with five of the seven regions posting gains.

The chemistry industry is one of the largest industries in the United States, a $770 billion enterprise. The manufacturing sector is the largest consumer of chemical products, and 96% of manufactured goods are touched by chemistry.

The U.S. CPRI was developed to track chemical production activity in seven regions of the United States: Gulf Coast, Midwest, Ohio Valley, Mid-Atlantic, Southeast, Northeast and West Coast. It is measured using a three-month moving average. Thus, the reading in September reflects production activity during July, August and September.