3. Computing and crediting interest. Under subsection 2, interest shall must be computed on the daily balances in the account from the date of receipt to the date of disbursement and shall must be credited to the account as of the last business day of each quarter of a calendar or fiscal year. If the such an account is closed or discontinued before the last business day of a quarter of a calendar or fiscal year, interest shall must be computed and credited as of the day the account is closed or discontinued. For the purposes of this section calculating interest under subsection 2, the mortgagee may take into account debit balances resulting from advances and may elect to compute interest on the basis of the actual number of days in each quarter and year, or on the basis of a 30-day month and a 360-day year. At least once a year, the mortgagee shall give the mortgagor a statement showing the interest credited on the escrow account during the period which that the statement covers.