At any time, Rowland Water District may require a deposit. For New Applicants the deposit is calculated and adjusted annually, based on the average total bill for customers who have the same size meter and who are also in the same water rate category multiplied by Two Hundred Fifty Percent (250%). For existing customers the deposit is calculated based on the average total bill of that particular customer for at least three (3) billing periods and no more than twelve (12) billing periods multiplied by Two Hundred Fifty Percent (250%).