The 2013 Wyoming Manufacturers Directory, just released by Illinois-based Manufacturers' News found oil and gas extraction accounted for the biggest employment jump, at 6.3% to 10,219 jobs. Coal mining was second, accounting for 6431 jobs, up a half per cent year-on-year.

Coming in third was industrial machinery and equipment, representing 3707 of the state's jobs, an increase of 4.2%.

MNI, which has been surveying industrial numbers since 1912, also said Wyoming gained 640 manufacturing jobs overall between October 2011 and October 2012.

The state has about 1200 manufacturers that employ 33,463 workers.

“Wyoming has perhaps the nation's most favorable tax structure for businesses, and has enjoyed an energy boom in recent years,” MNI president Tom Dubin said.

“The state's significant oil, gas and coal extracting industries have led the way in the creation of new jobs.”

Taking the top spot for manufacturing employment was Gillette, with 6058 jobs – up 1.5% over the prior year.

Casper was second with 4276 jobs, down a half per cent, and employment was steady in Wright with 3237 industrial jobs.

Rock Springs and Green River, both also home to major coal operations, reported a respective 2663 jobs, with no significant change, and 2481 jobs, up 1.4%.

Wyoming is consistently the top US coal producing state.

According to the Wyoming Mining Association, the state’s mines produced 432,481 billion tons in 2009 (the latest full year of data available) and directly employed 6822 people.

Among the largest operations by production are the Belle Eyr mine, the Eagle Butte mine and the Buckskin operation.