Actually Montek Singh only Serve RBI up 1991-1994, after that up 96-

MONTEK SINGH AHLUWALIA 1991-1994 FINANCE SECRETARY 18 ONE RUPEE DESCRIPTION OBVERSE:- * PICTURE - Ashoka Pillar Capital in rupee coin * LEGEND - Secretary Ministry of Finance * SIZE - 63 x 96 mm & NUMERAL - '1' in two places * VALUE LEGEND - English and Hindi & SL No in bottom right REVERSE :- * PICTURE - Rupee coin dated 1991 or 1992 or 1993 or 1994 * LANGUAGE PANEL- 13 Indian Languages & Oil rig 'Sagar samrat' * WATER MARK - Ashoka Pillar Capital in Round window * COLOUR - Blue, brown, pink, purple & multicolour NO. PREFIX INSET YEAR REMARK 1 K to M B 1991 Secretary Ministry of Finance 2 M & N B 1992 Secretary Ministry of Finance 3 N B 1993 Secretary Ministry of Finance 4 N B 1994 Secretary Ministry of Finance