(5) The price at which the gas is sold must be taken into account, directly or indirectly, in the issuance of the order or certificate by the Federal Power Commission. Price increases after February 1, 1975, are presumed to take increases in tax liabilities into account unless the taxpayer demonstrates to the contrary by clear and convincing evidence that the increases are wholly attributable to a purpose or purposes unrelated to the repeal of percentage depletion for gas (e.g., where the record of the Federal Power Commission clearly establishes that the Commission did not take the repeal into account). Increases to reflect additional State and local real property or severance taxes, increases for additional operating costs (such as costs of secondary or tertiary processes), adjustments for inflation, increases for additional drilling and related costs, or increases to reflect changes in the quality of gas sold, are some examples of increases that are not attributable to the repeal of percentage depletion for gas. In the absence of a statement in writing by the Federal Power Commission that the price of the gas in question was not in fact regulated, the requirement of paragraph (c)(5) of this section is deemed to have been met in any case in which the Federal Power Commission issued an order or certificate approving the sale to an interstate pipeline company or, in a case in which it is established by the taxpayer that the Federal Power Commission has influenced the price of such gas, an order or certificate permitting the interstate transportation of such gas. In addition, an emergency sale of natural gas to an interstate pipeline, which, pursuant to the authority contained in 18 CFR 2.68, 2.70, 157.22, and 157.29, may be made without prior order approving the sale, is deemed to have met the requirements of paragraph (c) (3), (4), and (5) of this section. For purposes of meeting the requirements under this paragraph, it is not necessary that the total gas production from a property qualify as regulated natural gas. The determination of whether mineral production is regulated natural gas shall be made with respect to each sale of the mineral or minerals produced.