EXAMPLE
Customer A is located at 200 feet on an extension.
Customer B is located at 120 feet.
Investment amount ($ amount to be invested by utility per customer) = $600
Cost of extension = $6000
Average cost of extension per foot = $30
If, after deduction of the investment amount for any customer, the contribution required from that customer is a negative amount, the customer shall make no contribution, but the utility shall make an investment on behalf of that customer equal only to that customer's share calculated as described above.
In the formulas stated below the account numbers listed are from the Uniform System of Accounts for water utilities, contained in Chapter 61 of these rules (65-407 C.M.R. 61).
The basic formula for determining the investment amount (IA) is:
IA = IF x ACR
The formula for determining the investment fact (IF) for a non-investor owned utility is:
The formula for determining the investment factor (IF) for an investor owned utility is:
Where
ACR = Average Annual Customer Revenue per customer for the applicable class or meter size subclass, divided by the difference of 1 minus the percentage determined in the most recent rate case, expressed decimally, of the utility's revenue requirement paid for fire protection by the municipality in which the main extension is located. If a utility is not able to determine average revenue for a particular class or meter size subclass because of insufficient experience, it shall use an estimated average revenue, based on average usage amounts from other water utilities and approved by the Director Technical Analysis of the Commission.
D = Depreciation Expense from Account 403.
A = Amortization Expense from Account 407.
I = For non-investor-owned utilities, total Income Deductions from Accounts 427, 428, 429 and contractual appropriations of income included in Account 436. For investor-owned utilities, the weighted cost of debt times the rate base allowed in the utility's last rate case, unless a different amount is approved or set by the Commission or the Director of Finance.
R = Operating Revenues from Accounts 460 to 474 inclusive.
T= Total Non-operating Income from Accounts 415 to 421 inclusive and Account 426.
C = Overall cost of capital for non-investor owned utilities, expressed as a decimal. Unless otherwise approved or set by the Director of Finance or the Commission, the cost of capital shall be the average interest rate for the first 15 years of the most recent issues of the Maine Bond Bank for a serial bond, assuming equal annual principal payments.
CD = Cost of debt for an investor-owned utility, weighted by the debt ratio, expressed as a decimal. Unless otherwise approved or set by the Director of Finance or the Commission, the cost of debt and the debt ratio shall be those approved in the utility's most recent rate case.
CE = Cost of equity, weighted by the equity ratio, expressed as a decimal. Unless otherwise approved or set by the Director of Finance or the Commission, the cost of equity and the equity ratio shall be those approved in the utility's most recent rate case.
FIT = The utility's marginal federal income tax rate allowed in its most recent rate case, expressed as a decimal, unless a different tax rate is approved or set by the Director of Finance or the Commission.
P = Principal payment percentage annually, expressed as a decimal. Unless a different amount is approved or set by the Director of Finance or the Commission, the amount shall be .067 (15 years).
SIT = The utility's marginal state income tax rate allowed in its most recent rate case, expressed as a decimal, unless a different tax rate is approved or set by the Director of Finance or the Commission.
The investment amount shall be calculated each year on or before July 1. With the approval of the Commission, a utility may apply an adjustment to both the numerator and denominator of the fraction which determines the ratio of investment costs to total income in order to correct for past overinvestment in line extensions under the former investment factor contained in this chapter prior to its amendments effective May 7, 1986.
65- 407 C.M.R. ch. 65, § 1