Many investors, especially during earnings season, seem to focus on the income statement. How much revenue was there? How much net income was there? Yet that focus can be dangerous, because the balance sheet actually tells us a lot about how the company is doing, and what it's likely to be doing in the not-too-distant future. Today, I'll focus on two balance sheet line items, accounts receivable (A/R) and inventories, and how they relate to sales.

In Thornton O'Glove's book Quality of Earnings, he calls the analysis of A/R and inventory growth relative to sales the "best method" to get ahead of Wall Street analysts:

One of these simple ploys -- the best method I have ever discovered to predict future downwards earnings revisions by Wall Street security analysts -- is a careful analysis of accounts receivables and inventories. Learn how to interpret these ... a larger than average accounts receivable situation, and/or a bloated inventory. When I see these, bells go off in my head.

If A/R goes up significantly faster than sales, then the company could be stuffing the channel, pulling sales in from the future. It can only do so for so long before customers get fed up and stop buying for a while. Then the company ends up missing revenue and earnings, and the stock price gets whacked.

Similarly, if inventory is rising significantly faster than sales, that could mean demand is slowing down, and a big inventory writedown might be coming. Alternately, sales will be hurt when the company uses large markdowns just to clear out inventory.

Note that I'm not talking about normal business-cycle stuff. Many retailers build up inventory prior to the holiday season in order to meet expected demand. That's normal. Instead, I'm looking for a big disconnect between the growth of sales and the growth of A/R or inventory. That's a potential sign of a risky investment, and it makes me dig a bit deeper to see what's going on.

Let's apply this to GameStop (NYSE: GME), the video game retailer. Here's what the company has reported for the last four quarter period, and for the last two year-over-year periods. I've also included a couple of others for comparison's sake.  {Copy: I suggest leaving the two empty rows in the table, as it makes the data easier to read. -- Jim}

Metric

GameStop

Best Buy (NYSE: BBY)

Target (NYSE: TGT)

Revenue growth, TTM

3.7%

9.2%

3.1%

A/R growth, TTM

10.4%

10.7%

(15.8%)

Inventory growth, TTM

2.7%

15.5%

2.7%

       

Revenue growth, year ago

10.0%

12.3%

(0.6%)

A/R growth, year ago

(34.2%)

167.7%

(8.7%)

Inventory growth, year ago

13.3%

9.6%

2.9%

       

Revenue growth, 2 years ago

36.4%

11.3%

4.9%

A/R growth, 2 years ago

104.6%

12.0%

24.7%

Inventory growth, 2 years ago

35.9%

16.4%

10.1%

Source: Capital IQ, a division of Standard & Poor's; TTM = trailing-12-month.

As you can see, two years ago was a terrible year for GameStop collecting what it was owed, as it let A/R grow nearly three times as much as sales grew. Sales growth has slowed down since then, but A/R is still 50% higher than it was before that huge surge. Not a good position to be in. Best Buy is in a similar position, letting A/R grow an astounding 13 times faster than sales grew a year ago. Investors should watch out for A/R write offs growing in the future, unless management knuckles down and collects the money Best Buy is owed. Target's done fairly well the last couple of years, but two years ago it let things slip. But, A/R has actually declined for the last two years, so management seems to have recognized the danger early and nipped it in the bud.

Pay attention to the balance sheet, plug a few numbers into a simple spreadsheet, and, according to O'Glove, you can get ahead of Wall Street. This easy analysis, along with a bit of thought, gives you the potential to save yourself the heartache of seeing your investment get sharply cut when a company reports a "surprisingly" disappointing quarter.

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Best Buy is a Motley Fool Inside Value recommendation, a Stock Advisor selection and Motley Fool Options has recommended a bull call spread position on it, as well as recommending writing covered calls on GameStop. Plus, the Fool owns shares of Best Buy. Try any of our Foolish newsletter services free for 30 days.

Fool analyst Jim Mueller doesn't have a position in any company mentioned. He works with the Fool's Stock Advisor newsletter service. The Motley Fool is investors writing for investors.