The 2005 assessment report by the Jewish People Policy Planning Institute predicts that Israel will represent an increasing share of the Jewish people: by 2020, Israel's Jewish population will grow by about a million, while the number of Diaspora Jews will shrink by around half a million. The global Jewish population will increase from today's 13 million to 13.5 million.
The JPPPI report, which will be presented at the next cabinet meeting, indicates that Diaspora communities are continuing to dwindle as a result of low birth rates and intermarriage rates of more than 50 percent. The report's authors do not anticipate mass immigration to Israel in the foreseeable future and note that 90 percent of the world's Jews reside in developed countries and enjoy a standard of living similar or higher than Israel's.
Bakrat writes elsewhere that even without much immigration, Jewish communities in the Diaspora will shrink, often dramatically.
The Jerusalem-based institute predicts that there will be 6.25 million Jews in Israel in 2020, compared to 5.25 million Jews today. In North America the number of Jews is expected to remain stable, at about 5.5 million. The number of Jews in Europe is expected to drop from 1.25 million to 1 million. In the former Soviet Union, the number of Jews is expected to shrink from 380,000 to 180,000.
The rate of assimilation is expected to be slightly less than 50 percent in the U.S., 60 percent in Germany and Hungary, and 80 percent in the former Soviet Union.
So far as I know, Israel is unique in bucking the trend of diaspora-founded nation-states to see their populations decline relative to their diasporas. Armenia, Lebanon, and Haiti, to name but a few diasporic homelands, have remained countries of net emigration, the tendency to leave if anything growing over time. For Jews, assimilation and intermarriage play a role in the growth of Israel, but only a partial role; if anything, they bolster numbers by creating an extended Jewish population. Even so, the centre of gravity of Judaism continues its inexorable shift towards Israel.