That relates to the performance of securities in which Citigroup invests the deposits it gathers. "If interest rates increase and the securities portfolio will deteriorate in value that will create a whole lot of DTAs in a hurry, so much of it is beyond their control," Willens told TheStreet in a telephone interview Monday. Most investors and analysts still don't appear to be focusing much on the DTA, and RBC Capital Markets analyst Gerard Cassidy offered no qualifier while noting its $1.1 billion reduction during the quarter. Citigroup shares were up by more than 4% Monday and were headed higher again in pre-market trading Tuesday, as the shares have under-performed in 2014 and first quarter earnings beat expectations. Oppenheimer's Chris Kotowski called Citi "one of the few genuine values remaining in the banking sector" in a report published late Monday. And Citigroup CEO Mike Corbat made clear the tax issue is on his radar, bringing it up on two occasions during the call without being asked.