Section 19B(a) in All India Services (Death-Cum-Retirement Benefits) Rules, 1958
(a)the balance in the said account should not have fallen below [Rs. 4000] [Substituted/inserted vide Notification No. 25011/37/80-AIS(II) dated 26.02.1981 (GSR No. 276 dated 14.03.1981)] at any time during the said period of three years.