The Revenue Department is trying to locate 9 lakh business entities which have stopped filing service tax returns, with a view to improving collections, meeting Rs 82,000-crore target in 2011-12 and to ascertain whether there is any tax evasion. There are 15 lakh registered service tax payers in the country. According to the Central Board of Excise and Customs (CBEC) Chairman SD Majumdar, only six lakh service tax payers are filing returns.