By Taylor Kuykendall and Ashleigh Cotting

Data feature produced by S&P Global Market Intelligence research groups in cooperation with the news department to highlight emerging trends and topics of interest.

Now that Peabody Energy Corp. has filed for bankruptcy, more than two-thirds of the coal produced in the Powder River Basin comes from a company that has recently filed for bankruptcy.

According to an analysis of SNL Energy data, about 44.3% of the coal produced in the U.S. came from a company that has filed for bankruptcy court protection since 2012. More than 69% of the coal produced in the Powder River Basin came from coal companies recently filing bankruptcy.

In Wyoming, home of Peabody's North Antelope Rochelle mine, the largest in the nation, nearly three of every four tons mined came from a coal company on the bankruptcy list. The North Antelope Rochelle mine produced 109.3 million tons of the 896.8 million tons of total domestic coal produced in 2015.

Peabody also holds major coal-producing assets in the Illinois Basin. With the latest bankruptcy filing, now about 28.9% of coal from the Illinois Basin comes from a coal company recently filing for bankruptcy court protections.

The data may slightly underestimate the figure as it examines the production data based on current ownership, and through asset sales, some mines sold in bankruptcy may have been sold to solvent companies not noted on SNL Energy's compiled bankruptcies list. The analysis of production comes from fourth-quarter 2015 data, the most recent full data set available from the U.S. Mine Safety and Health Administration.

According to a recent report from Fitch Ratings, the filing pushed the U.S. metals and mining loan default rate to 29% from 25%.

Peabody's focus on thermal coal mined primarily from Illinois Basin and Powder River Basin mines allowed the company to avoid many of the challenges of producers with a heavier focus in eastern U.S. coal basins. However, despite each of its operations being cash flow positive, Peabody has struggled under the weight of debt it took on to purchase Macarthur Coal Ltd. in Australia, a major leap into metallurgical coal markets.

Prices for met coal collapsed after hitting highs over $300 tonne in 2011. Only recently did the met coal benchmark reverse course and edge back up to $84/tonne.

Peabody faced additional challenges when a deal struck with Bowie Resource Partners LP did not go through smoothly. The deal, which Peabody said was terminated, would have provided the company with additional liquidity in exchange for its New Mexico and Colorado assets.

Opponents of the coal industry pointed to Peabody's filing as evidence the entire industry was flailing.

"Peabody Energy's bankruptcy is a harbinger of the end of the fossil fuel era," said Jenny Marienau, U.S. divestment campaign manager with 350.org. "Peabody is crashing because the company was unwilling to change with the times — they doubled down on the dirtiest of all fossil fuels, and investors backed their bet, as the world shifted toward renewable energy. They have consistently put profit over people, and now their profits have plummeted. Our world has no place for companies like Peabody."

Peabody, however, writes in its filings that it is simply reorganizing for stabilized markets in the future — a claim also made by other large coal companies that later decided to sell or liquidate assets. The company assured customers in a letter that it would continue to operate in the normal course of business throughout the bankruptcy.

"Peabody has an unmatched asset base, strong underlying operations, an outstanding workforce, a new management team and geographic diversity," the letter states. "During this process, we expect to continue to do what we do best: mining coal, loading trains, restoring lands and maintaining our activities in a largely business-as-usual fashion."

Peabody also assured employees, community partners, investors and others it was working to continue to maintain a global presence.

"The pressures affecting the global coal industry in recent years have been extreme and, indeed, unprecedented, creating significant balance sheet issues for the company," the company wrote in a letter to community partners. "Industry pressures include a dramatic drop in the prices of metallurgical coal for international steel making, weakness in the Chinese economy and overproduction of domestic shale gas. But coal will remain as an essential part of the energy mix … and Peabody is here to stay."