The government today announced a 5% bonus on new monthly post office deposits.The bonus will be applicable for Post Office Monthly Income Accounts opened on or after December 8, the finance ministry said in a statement.The government will also offer tax relief on deposits with a maturity of five years and senior citizen savings scheme, the statement said.The measures are aimed at promoting post office small savings, which has been witnessing a sharp decline due to lower return and lack of tax benefit for most of the schemes.There has been a demand from different sections for restoring the element of bonus on monthly post office savings. There has also been a demand that the Five Year Post Office Time Deposit Account and the Senior Citizens Savings Scheme should enjoy the same tax treatment as is applicable to five year bank deposits.