Dear Abhrajita: If leave salary is to correspond with the salary accruing at the time the leave is earned, that would render the calculations cumbersome and otiose if you reckon the effort involved, as the amount for each day's leave would vary with every pay band in which the leave was earned. It would be a very complicated book keeping. Next, when you are availing leave, payment is made on the current salary, so for encashment it has to be on same basis and it cannot be of lesser value. Moreover, since leave is encashed/availed in the present context , it is only the present salary which can form the basis.