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 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 Green Mountain Coffee Roasters (Nasdaq: GMCR), the fast-growing coffee company. 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.

Metric

Green Mountain Coffee Roasters

Starbucks (Nasdaq: SBUX)

Peet's Coffee & Tea (Nasdaq: PEET)

Revenue growth, TTM

68.8%

4.3%

11.7%

A/R growth, TTM

88.1%

(4.3%)

27.7%

Inventory growth, TTM

80.4%

(29.4%)

26.9%

       

Revenue growth, year ago

56.1%

(4.3%)

9%

A/R growth, year ago

81.7%

3.9%

15%

Inventory growth, year ago

63.6%

6.2%

7.7%

       

Revenue growth, 2 years ago

45.3%

14.9%

17.6%

A/R growth, 2 years ago

32.7%

13.2%

23.1%

Inventory growth, 2 years ago

129.6%

0.8%

8.8%

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

Over the past couple of years, Green Mountain has consistently let A/R and inventory grow faster than sales, and inventory grew much faster two years ago. Not good. After three years of this, inventory is now 6.8-times larger than it was then, while sales are only 3.8-times larger. The company simply must reverse that trend, or it's going to end up writing down a bunch of inventory or try to push it out the door at deep discounts, with resulting hits to revenue, margins, and net income. Peet's isn't in the same situation at all, at least with its inventory. The A/R line, however, has consistently grown faster than sales, so this company needs to make a concerted effort to collect on the cash owed it. Starbucks, on the other hand, has kept tight control on these two items, despite last year's bit of divergence.

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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Green Mountain Coffee Roasters is a Motley Fool Rule Breakers selection. Starbucks is a Stock Advisor pick. Try any of our Foolish newsletter services free for 30 days.

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