In the late 19th and early 20th centuries, about 50,000 Indian laborers arrived in the islands to work on sugar plantations. Most recent immigrants come from neighboring islands. There has been steady internal migration from rural to urban areas. There was a substantial increase in emigration by Indians in the immediate aftermath of the coup of May 1987. There are no restrictions on emigration, as 40,000 have done so since 1987. Most of these emigrants were professionals or Indo-Fijians. In 1996, it was estimated that Indians emigrated at a rate of between 4,000 and 5,000 a year. In 1999 the net emigration rate was -3.78 migrants per 1,000 population.