If you are a supply chain geek like those of us here at SCDigest, you have to love the chart below, produced by the ocean industry analysts at Alphaliner.

It shows the historical relationship from 1990 (when global trade really started to take off) to 2012 of global GDP growth to increases in ocean container volumes worldwide.

Source: Alphaliner

As can be seen, over this period container volumes have grown significantly more in percentage terms versus global GDP, creating what has been called the "GDP multiplier." But that multiplier has been shrinking rapidlly, not surprisingly, as the increase in global trade growth versus global GDP has also been dropping sharply in recent years.

From 1990 to 1999, container volumes grew 3.5 times the rate of global DP growth, then declining to 2.7 times the GDP rate from 2000 to 2009.

Then a drop to a GDP multiplier of just 2.1 over the last three years. In 2012, the multiplier dropped even further, to only 1.5 times, with global container growth reaching an estimated 4.6% compared to GDP growth of 3.2%.

Add to this that global GDP estimates for 2013 have been dropping - just 3.3% growth this year, according to the International Monetary Fund this month, down from 3.5% it predicted in January, which itself was a weak number - and it sounds like the supply-demand balance will continue to favor shippers, as the ocean carriers continue to add capacity well above container growth rates.

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