(a) This account must include the cost of service company property, included in accounts 301 (§367.3010), 303 (§367.3030) and 389 to 399.1 (§§376.3890 to 367.3991), owned and used by the service company in its operations, and having an expectation of life in service of more than one year from date of installation.

(b) The cost of additions to, and betterments of, property leased from others, that are includible in this account, must be recorded in subaccounts separate and distinct from those relating to owned property. (See Service Company Property Instruction in §367.54.)