Question: How many tariff codes have a bts retail price of 2.553p/min?
Schema: create table table_10408617_5 (tariff_code varchar, bts_retail_price__regulated_ varchar, PRIMARY KEY (tariff_code))
SQL: select count(tariff_code) from table_10408617_5 where bts_retail_price__regulated_ = "2.553p/min"