The rule amendments modify and define the rules which prescribe accounting principles and procedures for the calculation of depreciation by gas utilities. Rule 25-7.045 is amended to eliminate the requirement for multiple copies of depreciation studies, provide a specific reference to the Uniform System of Accounts, and codify the Commission’s authority to require a depreciation study at a time set by the Commission. Rule 25-7.046 is amended to specifically reference the Uniform System of Accounts as the standard for depreciation accounts and new depreciation subaccounts.