Households moving from one town to another within Israel are leaving disadvantaged periphery towns behind and grouping together with people like themselves, a Bank of Israel study shows. "Internal migration has significant ramifications on ... suburbanization processes, changes in the make-up towns' populations, segregation processes and increased polarization between towns, infrastucture- and land-use patterns, and social aspects," the study found. Between 1983 and 1995, some 17 percent of Israeli families moved from one municipality to another. Socioeconomically "strong" families, the study said, left the big cities for suburban "community settlements" (yishuvim qehilatiyim); young, educated couples left "development towns" in the remote North and South; and the shift of stronger families to small, homogenous communities worsened trends toward segregation and threatened to aggrevate polarization and widen disparities between the educational systems of different towns. "This migration has important ramifications for policy, especially considering that for years the declared [national] policy attributed much weight to spatially spreading out the population, and even allocated notable resources in an attempt to influence individuals' place of residence," asserted the study's authors Kobi Braude and Guy Navon, of the central bank's research department. "Migration (incoming and outgoing) reached significant proportions in all localities, although there were great differences between localities in the balance of migration and its characteristics," they added. Net negative migration (those leaving the city minus new arrivals) came to 9% in Tel Aviv, 8% in Jerusalem, 4% in the rest of Gush Dan, and 5% in Haifa and the Krayot and 9% in peripheral development towns. The average education among those leaving the big cities is "significantly" higher than among those left behind, and - besides Tel Aviv - among the newcomers, as well. Parents moving their families from the city to small, well-established suburbs were particularly scholarly, having accomplished 14.1 years of schooling on average. Newcomers to Jerusalem averaged 13 years of education; to Tel Aviv 12.5; to Haifa and the Krayot 12.1; to development towns 11.9; and those moving from elsewhere into other parts of Gush Dan had only 11.5 years of schooling on average. Those leaving Jerusalem had 13.6 years of education on average; those leaving Haifa and the Krayot 12.9; those leaving Gush Dan 12.6; and ex-Tel Avivim had 11.7 years, as did those who left development towns. Among those left behind, Jerusalemites had 12.1 years of schooling; inhabitants of Haifa and the Krayot had 11.5 years; Tel Avivim had 10.9, while those staying put in communities elsewhere in Gush Dan had studied for 10.8 years and those left behind in peripheral development towns had 10 years. Braude and Navon found that the tendency to move to another municipality was higher the more wealthy and educated a family was, and initially lower the older the household became, but then the tendancy to move rose again above a certain age. The study included a sample of 17,199 Jewish Israeli households in which the parents were together in both 1983 and 1995, and excluded immigrants who arrived in the 1990s.