Still, I'm no fortuneteller, and these are just numbers. End-of-quarter DSO increased 8.0% over the prior-year quarter. For the last fully reported fiscal quarter, Synaptics's year-over-year revenue shrank 4.8%, and its AR grew 2.8%. So, let's get back to our original question: Based on DSO and sales, does Synaptics look like it might miss its numbers in the next quarter or two? Differences in business models can generate variations in DSO, and business needs can require occasional fluctuations, but all things being equal, I like to see this figure stay steady. Synaptics's latest average DSO stands at 73.2 days, and the end-of-quarter figure is 71.0 days. Similarly, a spike in the blue bars indicates a trend worth worrying about. When that red line (AR growth) crosses above the green line (revenue growth), I know I need to consult the filings. I prefer to look at end-of-quarter receivables, but I've plotted both above. The standard way to calculate DSO uses average accounts receivable. Data is current as of last fully reported fiscal quarter. Is Synaptics sending any potential warning signs? Take a look at the chart below, which plots revenue growth against AR growth, and DSO: Investors don't like revenue shortfalls, and employees don't like reporting them to their superiors. Why might an upstanding firm like Synaptics do this? For the same reason any other company might: to make the numbers. Alternately, it can indicate that the company sprinted to book a load of sales at the end of the quarter, like used-car dealers on the 29th of the month. However, AR that grows more quickly than revenue, or ballooning DSO, can, at times, suggest a desperate company that's trying to boost sales by giving its customers overly generous payment terms. Sometimes, problems with AR or DSO simply indicate a change in the business (like an acquisition), or lax collections. However, by considering the trends in AR and DSO, you can sometimes get a window onto the future. Alone, AR - the amount of money owed the company - and DSO - the number of days' worth of sales owed to the company - don't tell you much. It's an important step in separating the pretenders from the market's best stocks. In this series, we use accounts receivable and days sales outstanding to judge a company's current health and future prospects. However, certain clues may help you see potential stumbles before they happen - and before your stock craters as a result. There's no foolproof way to know the future for Synaptics ( NAS: SYNA) or any other company.