Yeridah exceeding Aliyah

This week, over 200 Jews from North America made aliyah dispite the war, as described here:

"A record-setting year of North American Aliyah continued Thursday..."

But this does not represent the trend. The number of persons making yeridah from Israel to the US during US fiscal year 2005 (10/1/2004 to 9/30/2005): 6,963

(Source: US Government).

I think this represents an increase over recent years, but the table that would have this information was unavailable.

By comparison, aliyah from the US to Israel during the first half (January 1 to June 30) of the following years:

2004: 601
2005: 564
2006: 589

(Source: Government of Israel)

The recent flights do not come close to counterbalancing the much larger numbers making yeridah. Clearly, there is still a pretty strong net migration from Israel to the US. Anyone want to speculate as to why?