Higher expenses and lower natural gas prices put a damper on two Lafayette-based energy company’s third-quarter earnings reports.

Stone Energy Corp.’s third-quarter earnings dropped to $23.7 million, or 48 cents per share, compared to $51.8 million, or $1.06 per share, a year earlier.

PetroQuest Energy Inc., which gets 77 percent of its production from natural gas, swung to a loss of $38.6 million, or 62 cents per share, compared to earnings of $3.7 million, or 6 cents per share, a year earlier. PetroQuest’s results included a $35.4 million non-cash “ceiling test write-down.” The Securities and Exchange Commission requires exploration and production companies to account for lower commodity prices and the drop in profitability of proved reserves. The company has taken non-cash charges of $109 million during the first three quarters of the year.

Stone said its average natural gas price fell to $3.25 per thousand cubic feet, compared to $4.48 for the third quarter of 2011. The figures included hedges, investments that offset drops in natural gas prices.

PetroQuest’s average natural gas price dropped to $2.26 per thousand cubic feet from 3.27 a year ago. The price included hedges.

Stone Energy’s results fell far short of Wall Street analysts’ forecasts. Analysts surveyed by Thomson Reuters expected earnings of 68 cents per share.

So did PetroQuest’s. Analysts surveyed by Thomson Reuters forecast earnings of 2 cents per share.