The bill forms shall show: Meter Reading. The reading of the meter at the end of the period for which the bill is rendered. Meter Reading Date. The date on which the meter was read. Units Used. The number and kind of units metered. Rate Schedule. The applicable rate schedule, or identification of the applicable rate schedule. If the actual rates are not shown, the bill shall carry a statement to the effect that, on request, the applicable rate schedule will be made available for examination. Amount. The gross or net amount, or both, of the bill. Payment Date. The date by which the customer must pay the bill in order to benefit from a discount or to avoid any penalty. Estimated Bill. A distinct marking to identify an estimated bill. Additional Billing Information. Any conversions from meter reading units to billing units or any calculations to determine billing units from recording or other devices, or any other factors used in determining the bill. In lieu of this information on the bill, a statement shall be on the bill advising that the information can be obtained by contacting the utility's principal office.