The last time this trade measure fell dramatically, it signaled the incoming global financial crash of 2007/2008. Now, it s happening again. Only this time, it s dropped to the lowest point in its history.The Baltic Dry Index tracks the cost of shipping  dry goods  around the world. Historically, it has served as a sort of  bellwether  for the global economy. Why? Well, if the prices fall, it means that trade is dropping. If trade is dropping, the economy is about to take a hit.Now, back in late 2013, the Baltic Dry Index was flying high at 2,330. And even last August, it was still at a healthy 1,222.This week, it crashed to just 354.Image via Business InsiderThe reason this should stop us all in our tracks, is that the last time this happened, it heralded the global financial crisis of 2008   from which many economies have yet to recover. And back then, it was still over 600.As Business Insider reports:There are several other occasions when the index has pointed to a big correction in the global economy. The Baltic Dry Index has existed in its current state since 1985, and it had its first big drop in mid-1986, just under a year before the Black Monday crash hit markets in 1987.In 1999 the Baltic Dry slumped to 12-year lows, very soon before the dot-com bubble burst. It slumped again to another massive low in 2001, around the same time the US economy fell into a recession that lasted until 2003.Does this mean we are definitely going to have a crash on the scale of 2008? No. It would be foolish to argue this test is infallible. But is it, together with other warning signs in the economy, something to which we should be paying serious attention? Absolutely.William White, former chief economist at Switzerland-based Bank for International Settlements, has warned that an epic debt tsunami is about to wash over the global economy, and that: The situation is worse than it was in 2007. Our macroeconomic ammunition to fight downturns is essentially all used up, The only question is whether we are able to look reality in the eye and face what is coming in an orderly fashion, or whether it will be disorderly. White is not alone. Banks like Goldman Sachs and the Royal Bank of Scotland have issued their own stark warnings about impending financial crisis. On top of that, Jeremy Penn, the Baltic Exchange s CEO, told The Telegraph: We are now at the stage where people are struggling to remember an era when it was this difficult, we ve gone through what it was like in the  90s, the  80s, and the  70s, so expressions like  living memory  start to apply, In short, we ignore these warnings at our peril.Featured Image via Flickr Creative Commons