A Robber went to rob a bank. What is the password ?

A Robber Went to rob a bank

On 28th Feb, 2012 (Tuesday) a robber went to rob a bank.
He threatened to kill the cashier if he didn't open the vault.
The cashier told that the vault is not opened with keys like in old days but by a password.
You can't kill me since I am the only one who knows the password
and everyday the password is different.
The robber shot the cashier, entered the password, opened the vault and robbed all the money.
What is the password???πŸ˜ŸπŸ˜³πŸ˜‡

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The Cashier says, The password is "Different"