Mumbai, Jan. 8 -- Shares of Bandhan Bank fell 6%, while Gruha Finance Ltd declined 14% after both firms announced merger through a share swap deal, which analysts expect to be expensive for former. Intraday, Bandhan Bank shares slumped as much as 6.04%, while Gruh Finance shares plunged 14.4%. At 9.51am, Bandhan Bank was trading at Rs 480.05 on BSE, down 4.2%, and Gruha Finance traded 13.5% lower at Rs 265 a share. India's benchmark Sensex index was trading at 35786.69, down 0.18% from its previous close....