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: Tupperware (NYSE: TUP) beat earnings this morning, but no one seems to care. Investors are instead focusing on management's promise to earn less money in the third quarter than they had been promised -- and selling the stock off to the tune of 12%.

So what: Tupperware reported earning $1.03 per share in Q2, a 12% increase over last year's haul. But it took a 19% increase in revenues to produce this profit, highlighting weaker profit margins.

Now what: Between that trend of profitability slipping, and Tupperware's recent inability to produce free cash flow at the level it claims for "GAAP profits," I can't blame investors for starting to lose faith in the company. With just over $200 million in FCF generated for the past 12 months, Tupperware shares now sell for a rich 22 times multiple to these cash profits. That's pricey relative to analyst expectations of 15% long-term profit growth at the company -- and Tupperware's 1.7% dividend yield isn't enough to make up the difference.

Long story short: I'd more likely be short this stock than long.

Disagree? Think Tupperware's going to pop the top in the third quarter? Add it to your Watchlist and see if you're right.

Fool contributor Rich Smith does not own (or short) shares of Tupperware. The Motley Fool owns shares of Tupperware Brands. 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.