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 dry bulk shipper DryShips (NASDAQ:DRYS) are getting torpedoed as much as 6.7% today following continued softness in the Baltic Dry Index, or BDI, and disappointing economic news out of China.

So what: The BDI measures the global daily spot rates for dry shipping. DryShips has made it clear in conference calls and interviews that the company is shifting its strategy toward operating based on the BDI and letting fixed-rate contracts expire. For this strategy to pay off for DryShips, the BDI needs to move up and not down.

Today, the BDI was off by 1.9%, to a reading of 970. For perspective, just a week ago the same index was at a reading of 1098. This comes out to an 11.7% plunge.

Now what: Contributing to these deteriorating rates was weaker than expected economic news from China. DryShips has said in interviews, press releases, and conference calls that the No. 1  factor by far affecting the BDI is China. Any slowdown in China is therefore not good for DryShips.

Seasonally adjusted GDP growth for the first quarter was reported at 1.5%, compared to 1.8% in the fourth quarter of last year. The concern is that deceleration is taking place and the 7.5% original target cited by China will be missed. Barclays Bank lowered its target from 7.3% to 7.2%. Meanwhile, Premier Li Keqiang said, "We will not take, in response to momentary fluctuations in economic growth, short-term and forceful stimulus measures." This means its economy is on its own.

The news is bad for DryShips. CEO George Economou about a month ago expected a "hot" dry shipping market over the next three months; instead, the dry shipping market has been cooling down ever since. If DryShips continues to be proven wrong, it calls into question Economou's forecasts for a red-hot market to exist in the fourth quarter and an "explosion" for the dry shipping market in 2015. It will be interesting to see what updated comments the executives of DryShips have in their next earnings release and conference call, which should come in the first weeks of May.