Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Blucora Inc (NASDAQ:BCOR) are trading 9% lower today after plunging to an early loss of over 13%. Investors are not happy that the company has produced weak guidance for the second quarter, despite the fact that it came through with decent earnings.

So what: Blucora reported its first-quarter results last night, which showed revenue of $216.2 million -- a 31% year-over-year gain -- and earnings of $1.12 per share. Analysts had expected $217.9 million in revenue and $1.03 in EPS, which means that Blucora beat the bottom-line estimate but fell a little short on the top line.

However, Blucora's guidance for the upcoming second quarter is what's gotten investors freaked out: the company now expects $135 million to $145.5 million in revenue, against Wall Street expectations of $163.4 million, and projects that its EPS will range from $0.46 to $0.53, which again falls far short of Wall Street's $0.64 EPS expectation.

Now what: Blucora shareholders have already suffered a gut-wrenching drop this year -- the stock had nearly quadrupled since the start of 2011 before crashing to a 40% loss in 2014. However, its forward guidance is pretty darn weak, as Blucora projected higher EPS  for second quarter of last year at a range of $0.51 to $0.55, despite expecting lower revenue than it does this time around.

Dwindling margins are never good news, but it's also worth noting that Blucora's price-to-free-cash-flow ratio is lower than it's ever been at 8.4, which indicates that focusing solely on EPS might not be the best way to assess this stock. Do a little digging today and you might find that this abandoned former growth stock could become a winner once again.

Alex Planes has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.