Demographics of Turkey are available for the Kurdish population, because the Turkish government has outlawed ethnic or racial censuses. An estimate by the CIA World Factbook places their proportion of the population at approximately 18%. Another estimate, according to Ibrahim Sirkeci, an ethnic Turk, in his book "The Environment of Insecurity in Turkey and the Emigration of Turkish Kurds to Germany", based on the 1990 Turkish Census and 1993 Turkish Demographic Health Survey, is 17.8%. Other estimates include 15.7% of the population according to the newspaper "Milliyet", and 23% by Kurdologist David McDowall. The Minority Rights Group report of 1985 (by Martin Short
Population exchange between Greece and Turkey Minor population. To this day, Greece and Turkey still have properties, and even villages such as Kayaköy, that have been left abandoned since the exchange. Population exchange between Greece and Turkey The 1923 population exchange between Greece and Turkey (, ) stemmed from the "Convention Concerning the Exchange of Greek and Turkish Populations" signed at Lausanne, Switzerland, on 30 January 1923, by the governments of Greece and Turkey. It involved at least 1.6 million people (1,221,489 Greeks from Asia Minor, Eastern Thrace, the Pontic Alps and the Caucasus, and 355,000 Muslims in Greece), most of whom were forcibly made refugees