Thor's products range from small camper trailers to giant luxury motorhomes like this Thor Tuscany. Source: Thor Industries.

Recreational-vehicle giant Thor Industries (THO -0.16%) reported earnings for the quarter ended July 31 after the bell on Monday. Here's what you need to know.

The key numbers
Thor reported a net profit of $69 million, or $1.31 per share, up 3% from a year ago. Revenue was $1.06 billion. Both numbers fell short of Wall Street estimates.

Thor's shares fell almost 6% in trading on Tuesday.

A small year-over-year gain despite a difficult comp
Thor's revenue of $1.06 billion was actually up 2% versus the year-ago quarter. But sales of both towable and motorized RVs fell versus last year, and that was a point of concern for investors. Recreational vehicles are big-ticket items, and like similar products (boats, for example), sales can fall very quickly at the first sign of economic weakness.

The small increase in revenue was attributed to the acquisition of Postle, an aluminum supplier that Thor acquired for $144 million. That acquisition became official on May 1 of this year.

Gross margins also rose, to 16.2% from 14.6% a year ago. Thor attributed that increase to several factors, including a drop in the net costs of some imported materials and improvements in warranty costs as a percentage of sales.

CEO Bob Martin noted that the comparison to the year-ago quarter was a somewhat difficult one for Thor, suggesting that this past quarter might have been better than it looked. Last year, the company realized a gain on the sale of some property and had a lower effective tax rate, Thor said in a statement. Taken together, they were worth about $0.12 a share.

Digging deeper: Early signs of a weakening market?
As noted above, Thor operates in two key business segments. Its biggest revenue generator are towable RVs, which range from simple pop-up trailers to elaborate Airstream units that sell for well into six figures. Thor's sales of towable RVs generated $802.2 million in the quarter, down 3% from a year ago. But the segment's pre-tax income was up 2%, to $85.7 million, largely on gains related to more favorable tariffs on imported raw materials.

Thor is a big producer of motorized RVs. The company produces motorhomes ranging from small units built on heavy-duty pickup frames to full-blown bus-sized mobile mini-mansions. Total sales numbers are fairly small, but these vehicles are expensive. The motorized RV segment generated $216.4 million in sales in the quarter. That was a small drop from a year ago, but pre-tax income rose 33% to $19.9 million. Thor said that was due to "improved labor and warranty costs" as well as the change in tariffs.

A mixed outlook for the year ahead
Martin and his management team make a point of maintaining a strong cash position. It's still strong: Thor had $183.5 million on hand as of July 31.

This quarter represented the end of Thor's fiscal year. Looking ahead to fiscal 2016, Executive Chairman Peter Orthwein said in a statement that "we see a number of macro uncertainties that may impact our results, from the recent volatility of financial and commodity markets to the inherent uncertainty surrounding the actions of the Federal Reserve and presidential elections, which may weigh on consumer behavior."

Thor is also concerned about weakness in Canada's economy and the relative strength of the dollar, he said. Canada is a significant market for Thor. 

But, Orthwein said, "As these challenges are eclipsed by the opportunities we see in our industry, we feel confident in the future of Thor."