No matter what their officials tell, it is certain that drop of sales led to that. Vodafone might be the worst managed telecom related company in Turkey. There was a wide margin between them and Avea in the number of subscribers in Telsim days, now they are almost becoming the smalles gsm operator in Turkey.
I believe there is no need to tell that they have no Value added services or innovative plans for this market. Some people in UK might be writing an exit plan at the moment.