Dear Vivek, Your question is like "How long should a piece of string be to tie up a person?" Without knowing details such as what type of benefits the bank is providing, what the attrition rate is, etc., even experienced persons cannot give you a figure. Hence, the more information you can provide, the better for people to respond positively. Kindly see the exchange of views at
https://www.citehr.com/319453-key-learning.html to realize the futility of posting short messages like your first message. Have a nice day.
Regards, Simhan