Being an investor in Alpha Natural Resources (NYSE:ANR), Arch Coal (NYSE:ACI), and Walter Energy (NASDAQOTH:WLTGQ) has been nothing but discouraging for the past couple of years.

ANR Chart

ANR data. Source: YCharts.

However, all three have gone from just discouraging to flat-out concerning. Not only are they not generating any returns for shareholders, but they aren't even generating enough of a return on its coal contracts to pay the interest payments on their debt. 

With EBITDA-to-interest expense ratios dropping below 1 and the market for coal continually looking weak, these companies will need to rely on their cash hoards to cover payments for the foreseeable future. Find out how long these companies can hold out for better days by tuning into the video below. 

Tyler Crowe has no position in any stocks mentioned. You can follow him at Fool.com under the handle TMFDirtyBird, on Google+, or on Twitter @TylerCroweFool.

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