After decades of steady decline, the total number of Jews in the world increased slightly in 2010, according to a study by the Berman Institute / North American Jewish Data Bank University of Connecticut.

The number of Jews outside Israel declined, but their number inside Israel increased, said study editor Prof. Sergio Dellapergola of Hebrew University.

The size of world Jewry at the beginning of 2010 was assessed at 13,428,300. World Jewry constituted slightly less than 0.2% of the world’s total population of 6.9 billion. This means that one in about 510 people in the world is a Jew. According to the estimates, between January 1, 2009 and January 1, 2010, the Jewish population increased by an estimated 80,300 persons, or about 0.6 percent. This compares favorably with the dismal 0.1% average growth rate in more developed countries, but is less than the average 1.5% rate in less developed countries.

Israel’s Jewish population overtook that of the US in the middle of the last decade, Dellapergola told Arutz Sheva’s Hebrew language website, and greater Tel Aviv’s Jewish population overtook that of New York City at about the same time. “Today, the number of Jews who live in metropolitan New York is about two million,” he said, “versus three million Jews in metropolitan Tel Aviv.”

The rise in the number of Jews in Israel is the result of immigration and new births, he said. “There is international immigration into Israel and the birth rate has increased also. An average Jewish family in Israel is larger than an average one abroad.”

Prof. Dellapergola dismissed as untrue the common assumption that secular families are not interested in bringing children into the world. “The secular Jewish family in Israel wants more than the Jewish family abroad.”

Israel’s Jewish population surpassed 5.7 million in 2010, comprising over 42 percent of world Jewry, according to the report. This represented a population increase of 95,000, or 1.7%, from  2009.

In 2009, the Jewish population of the Diaspora decreased by about 15,000 (-0.2%). The core Jewish population in the United States was assessed at 5,275,000 and was estimated to have diminished somewhat over the past 20 years, after peaking around 1990.

The report states that “Israel’s current Jewish population growth—although slower than during the 1990s—reflects a continuing substantial natural increase generated by a combination of relatively high fertility (2.9 children per Jewish woman on average in 2009) and a young age composition (26 percent under age 15 and only 11 percent age 65 and over as of 2008). Neither of these two drivers of demographic growth exists among other Jewish populations worldwide, including the United States.”

Prof. Dellapergola noted, however, that the Jewish nation has yet to recover from the Holocaust. Were it not for Germany’s genocidal war against the Jewish nation, he estimated, the total Jewish population in the world would have reached about 25 million by now.