Stats from the high seas: Stormy weather ahead

CMA CMG shipping.
David Bally | Wikipedia

If you wonder about which way the economy is going, you may want to take a gander at a new barometer based on ocean shipping freight.

It's a tad worrisome at this point.

"As freight goes so goes the economy," said Rosalyn Wilson, a senior business analyst with Delcan Corp. "It seems to be tripping up a little bit."

Indeed, this newly developed set of ocean freight data indicates exports are well below previous years. And imports, while starting the year fairly strong, are sputtering.

The stats are from INTTRA, an outfit that can best be described as an Orbitz or Expedia for businesses looking to move freight across oceans. Its booking services cover 49 shipping lines representing about 93 percent of the world's ocean-going container space. In conjunction with Cass Information Systems, a logistics number cruncher (among other things), INTTRA recently put four years of its booking data into index form, going back four years, and released it to the public.

"This gives us a global view of what's happening in the freight market," said Sandra Moran, vice president of product and industry marketing for INTTRA.

And what's happening?

Export-wise things are looking up. There was a 7.3 percent rise in container exports from the United States in October, following a 9.9 percent drop in September, according to the report.

But don't get too excited. Every month in 2013 posted lower export levels than 2012. For just the month of October, container exports were 9.2 percent below the same month in 2012, 19.2 below the 2011 level and 22.4 percent below 2010.

The tale is a little better for imports. With the economy coming back, container imports picked up 14.2 percent over the summer. But things slowed in September, posting a 4 percent drop, and October showed an 8 percent drop in traffic.

(Related: Busiest U.S. trade hubs)

"I expect this decline to carry into the first quarter next year because inventories are high," said Wilson, who provides INTTRA with commentary on the indexes. "We're seeing interest rates begin to change ... a new Fed chair, ... the cost of holding inventory is going to get higher. They (businesses) aren't going to build them."

Another, longer-lived, shipping index seems to be hinting at the same thing.

Port throughput data for the U.S. East Coast and West Coast, compiled by Drewry Maritime Research in London, also show some recent weakness.

"It's only one month so it's difficult to call it just yet," Simon Heaney, consultant and research manager for containers for Drewry, said via email. "However, you will have seen that consumer confidence has dropped following the shutdown and fears of a repeat next year, so it's fair to say there are some difficult headwinds."

It is important to note these indexes are dealing with containerized freight traffic as opposed to bulk cargo shipments, like coal and wheat. So it may not be a complete picture of trade between the United States and the rest of the world. Nevertheless, it is estimated that over 90 percent of the world's nonbulk cargo travels by container.

INTTRA and Cass plan to release their index measure on a monthly basis.

Allen Wastler is managing editor of CNBC Digital. Follow him on Twitter @AWastler. You can catch his commentary here and on CNBC Radio. And check out his fiction.