Kurds are the largest non-Turkish ethnicity at anywhere from 12-25 per cent of the population. The exact figure remains a subject of dispute; according to Servet Mutlu, "more often than not, these estimates reflect pro-Kurdish or pro-Turkish sympathies and attitudes rather than scientific facts or erudition". Mutlu's 1990 study estimated Kurds made up around 12 per cent of the population, while Mehrdad Izady placed the figure around 25 per cent. The Kurds make up a majority in the provinces of Ağrı, Batman, Bingöl, Bitlis, Diyarbakır, Elâzığ, Hakkari, Iğdır, Mardin, Muş, Siirt, Şırnak, Tunceli and Van; a near majority in Şanlıurfa Province (47%); and a large minority in Kars Province (20%). In addition, due to internal migration, Kurdish diaspora communities exist in all of the major cities in central and western Turkey. In Istanbul, there are an estimated three million Kurds, making it the city with the largest Kurdish population in the world. Non-Kurdish minorities are believed to make up an estimated 7–12 percent of the population.