Indonesia censuses

The number of North Sumatra-born migrants in other provinces increased from 188,326 in 1971 to 1,314,117 in 2005 (BPS 2006), the biggest numbers being in Riau, West Java and Jakarta. The 1990 census showed that nearly 300,000 people left the North Sumatra province in the five previous years, suggesting that in that relatively prosperous period Bataks became Indonesia s champion outmigrants (BPS 1994 35). 

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