One of the biggest questions at the end of 2013 was how the Treasury market would react to the reduction of bond buying that would result from the Federal Reserve's tapering campaign. If the Fed were to hold course to its stated intentions, its $45 billion monthly purchases of Treasury bonds would be completely wound down by the fourth quarter of 2014. Given that those purchases represented a very large portion of Treasury bond issuance at that time, it was widely assumed by many, me in particular, that the sidelining of such huge demand would push down the price of Treasury bonds. Without the Fed's bid, interest rates would have to rise.

But almost five months later, yields on the 10-year Treasury bond are 50 basis points lower than they were at the end of 2013, despite the fact that the Fed has officially trimmed its monthly purchases in half. Apparently, plenty of other buyers were prepared to fill the void. Many have concluded that Uncle Sam doesn't need the Fed after all. But a close look at international activity in the Treasury market reveals some odd patterns that should be explained.

Over the last six months Belgium has started to behave eccentrically, even by Belgian standards. No, the small country of 11 million has not decided to stop making chocolate or waffles. It has decided to increase its buying of U.S. Treasury bonds... in a very big way. According to latest U.S. Treasury Department data, since August of 2013 entities in Belgium have purchased and held a stunning $215 billion of U.S. Treasuries. This figure is equivalent to about half the country's annual GDP, and equates to almost $20,000 for every living Belgian. Prior to that time, Belgium had held its cache fairly steady at around $170-$190 billion. But by March, that total had increased by almost 130% (to $381 billion) in just seven months. The purchases represented 61% of the total increase in foreign holdings of U.S. Treasuries over that time frame. Given the fact that Belgium, as of last September, had less than 3% of the Treasury bonds held by foreign sources, this is strange behavior indeed.