The main decline is the Russian market, the four-and-a-half million Russian tourists who were coming have fallen in number by around 95%. The trigger was Turkey shooting down a Russian military jet which violated Turkish airspace last November, sparking a diplomatic crisis between the two countries.
The Kremlin seethed, barring Russian tour companies from selling package deals to Turkey. President Vladimir Putin told Russians to holiday elsewhere.
The two strongmen leaders - Mr Putin and his Turkish counterpart Recep Tayyip Erdogan - are still at loggerheads, although Mr Erdogan did send a note to his counterpart this week to mark Russia's national day, in the hope of healing wounds.
What's more, a series of bombings across Turkey in the past year has scared off many others. Since violence resumed with the PKK Kurdish militants last summer, attacks by them and by the Islamic State group have occurred nationwide, some targeting tourists in Istanbul.