Turkcell ( TKC - Get Report) said its user roll expanded 5.3% sequentially in the second quarter and 22% from a year ago. The Turkish cell-phone service provider said it had 25.6 million subscribers at quarter-end, up from 24.3 million in the first quarter. Postpaid subscribers totaled 5.2 million, and prepaid subscribers amounted to 20.4 million. The company said its added 1.35 million net new subscribers, while the so-called churn rate measuring customer defections rose to 2.6% from 2.5% in the first quarter. "During the first half of 2005, growth of total subscribers in the Turkish GSM market and, accordingly, the growth in our subscriber base, was higher than our expectations, mainly due to increased sales and marketing efforts in a stable macroeconomic environment," CEO Muzaffer Akpinar said. "However, there is no change in our subscriber growth expectations for the whole year. During this period, we introduced several acquisition campaigns as well as mass and segmented retention activities and loyalty programs to further increase customer satisfaction. We will continue to take necessary measures to maintain our leadership position in the market." Turkcell closed Thursday at $12.80.