Is this the canary in the coal mine?

In another sign that the effects of the US subprime crisis have spread globally, Bloomberg reports that global business air traffic fell 0.4 percent in June, the biggest number in 13 months.

Adding to that are the thoughts of Wal-Mart chief executive officer, Lee Scott, who told the Financial Times that there are signs the US contagion is spreading into global markets.

""It started in North America and [it] spread to Europe; the economic difficulties are now showing up in some of the developing countries as well," Scott said. "People are eating more sandwiches in Puerto Rico, and relying more on private-label products in the UK.

"Customers in many areas are buying cheaper cuts of meat for dinner and, similar to the US, people in other countries are eliminating [their] vacations and entertaining more at home."

Indeed, the latest figures show European economies are contracting with various parts entering recession.