(a) The term delayed items means items relating to transactions which occurred before the current fiscal year. It includes adjustments of errors in the income, operating revenue, and operating expense accounts of prior years.

(b) Delayed items shall be charged or credited to the same accounts which should have been charged or credited if the items had been taken up or adjusted in the period to which they pertain. When the amount of a delayed item is relatively so large that its inclusion in the accounts for a single month would seriously distort those accounts, it may be distributed in equal amounts to the accounts for the current and remaining months of the fiscal year.

(c) If the amount of any delayed item is relatively so large that its inclusion in the accounts for a single year would seriously distort those accounts, the utility, if so authorized by order of the commission, may carry to Surplus as much of the amount as may be authorized. In requesting such authority, the utility shall file with the commission the full particulars concerning each such item and the reasons which in its judgment indicate the propriety of such accounting.