Money considered as income for a month is not an asset for the same month. Any income added to a bank account is income for that month, and not a part of the account's asset value for the month. To figure the asset value of the account, subtract the income from the bank balance. For the following month(s) any remaining income in the account is an asset.
Example: On September 5th a pension check of $600 is deposited in a savings account with a $1000 balance. The new account balance is $1,600. Subtract $600 from the account balance, leaving an asset balance of $1,000 for September. During the month of September $500 is withdrawn. On October 5th another $600 pension check is deposited. The asset balance as of October 5th is $1,100. The $100 remaining in the account from September's $600 pension check is now an asset in the month of October.