Byproducts revenue exempt from taxation

Effective after December 31, 2000, for any given month, the allowed exemption of revenue derived from the sale of byproducts other than the sale of carbon dioxide for use in enhanced recovery of oil or natural gas may not exceed twenty percent of the sum of total gross receipts from the sale of synthetic natural gas during the month plus total gross receipts from the sale of byproducts during the month. Gross receipts from the sale of carbon dioxide for use in enhanced recovery of oil or natural gas are not subject to tax but are included in total gross receipts for the purpose of the percentage calculation.