What happened For the fourth day running, shares of Turkcell Iletisim Hizmetleri (NYSE: TKC), Turkey's largest cellphone company, jumped on Thursday, and were up 5.5% as of 10:45 a.m. Turkey's president, Recep Tayyip Erdogan, has been trying to halt the currency's slide by the strange tool of lowering interest rates in hopes of reducing inflation. That works out to about a 6% one-day appreciation in the value of the lira versus the dollar, or about the same amount that Turkcell stock is up today.