What happened 

Recreational vehicle retailer Camping World Holdings (CWH -1.09%) shed 23% last month, according to data provided by S&P Global Market Intelligence, compared to a nearly 3% decline in the broader market. 

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The drop put shareholders just behind the market over the past 12-month period while they had been up by as much as 60% in early 2018.

So what

March's decline came in a busy month for the business. Camping World restated its fourth-quarter earnings report on March 13. Yet that adjustment included just a single non-cash valuation change that resulted in a lower reported net loss for the period. 

An RV being towed.

Image source: Getty Images.

The company also made several dealership acquisitions as it pressed forward along management's goal of significantly expanding its store footprint.

Now what

Late in the month, Camping World announced that it had secured an expanded credit line from an investment bank, and the move highlights just how large a role debt plays in the company's ability to finance both its inventory costs and its aggressive expansion strategy. Long-term debt was at $916 million at the end of 2017, up from $626 million a year ago.

That burden isn't a big threat to profits today, but it could become one if interest rates rise quickly, or if the RV market cools off in 2018 following eight straight years of robust growth.