Section R746-401-2 - DefinitionsA. For purposes of these rules: 1. "Commission" shall mean the Public Service Commission of Utah.2. "Gross investment in utility plant devoted to Utah service" shall mean the Utah allocated portion of the total of the following types of accounts: Plant in service, property under capital leases, plant bought or sold, completed construction not classified, and experimental plant unclassified. The following types of accounts shall not be included: Plant leased to others, property held for future use, construction work in progress, and acquisition adjustments.3. "Book cost" shall mean the amount at which an asset is recorded in the books of the utility without deduction for accrued depreciation, depletion, amortization, etc.B. For purposes of these rules, public utilities are divided into the following categories: 1. Large utilities - a public utility serving an annual average of 20,000 or more customers or access lines in Utah as set forth in its most recent annual report on file with the Commission and wholesale electrical cooperatives.2. Small utilities - a public utility serving less than an annual average of 20,000 customers or access lines in Utah as set forth in its most recent annual report on file with the Commission.Utah Admin. Code R746-401-2