The US Chemical Production Regional Index (CPRI) slipped by 0.3% in April following a downwardly-revised 0.4% decline in March, data from the American Chemistry Council (ACC) trade group showed on Wednesday.

Chemical production fell across all US regions on a month-over-month basis, the group said.

The chemistry industry is one of the largest industries in the US, a $720 billion enterprise. The manufacturing sector is the largest consumer of chemical products, and 96% of manufactured goods are touched by chemistry.

Using a three-month moving average of the Federal Reserve data comparable to the CPRI, output of the nation’s overall manufacturing sector rose by 0.3% in April, following a 0.5% gain in March.

Within the manufacturing sector, output in several key chemistry end-use markets increased, including motor vehicles, aerospace, construction supplies, machinery, computers, plastic and rubber products, paper, textile mill products and furniture.

Also measured on a three-month moving average basis, chemical production was mixed.

Output slipped in several key segments including pharmaceuticals, organic chemicals, plastic resins and synthetic rubber.

Many segments, however, saw rising production. Some of the largest gains were in man-made fibers, adhesives, industrial gases, chlor-alkali and inorganic chemicals.

Compared to April 2011, total chemical production in all regions was up 0.3% and remained ahead year-over-year in all regions except the Gulf Coast, Mid-Atlantic and West Coast regions.

On a year-to-date basis (comparing the first four months of 2012 with those a year ago), chemical production was up 0.5% nationally.

All regions were ahead on a year-to-date basis except the Gulf Coast region.