SOFIA (Bulgaria), February 18 (SeeNews) – The average annual yield on a 30 million lev ($22.5 million/15.4 million euro) issue of five-year 4.25% Bulgarian Treasury notes fell to 4.74% at an auction on Monday from 4.87% in the previous auction held in November, though the issue was 2.8 times oversubscribed, the central bank said.