Exchange rate movements can have large effects on the measured NIIP. For example, the current account deficit in 2007 was about $730 billion, which means we borrowed around 3/4 of a trillion dollars from foreign countries in 2007 alone. Naturally this causes the NIIP to decline: the world's largest debtor country goes more deeply into debt. However, the dollar depreciated almost 10% during the year, and most US assets held abroad are denominated in foreign currency. The BEA estimates a resulting rise in the dollar value of these assets of almost $440 billion, which it adds to the US NIIP.