; and (B) each retail natural gas supplier shall submit to the Secretary a report, in accordance with regulations promulgated by the Secretary, demonstrating that the retail natural gas supplier has achieved cumulative natural gas savings from measures (adjusted to account for any attrition of savings measures implemented in prior years) in each calendar year of such reporting period that are equal to or greater than the applicable performance standard. (2) Performance standards for 2021 through 2035 For each of calendar years 2021 through 2035, the performance standards are as follows: Calendar Year Cumulative Electricity Savings Percentage Cumulative Natural Gas Savings Percentage 2021 1.00 0.50 2022 2.00 1.25 2023 3.00 2.00 2024 4.25 3.00 2025 5.50 4.00 2026 7.00 5.00 2027 8.50 6.00 2028 10.00 7.00 2029 11.50 8.00 2030 13.00 9.00 2031 14.75 10.00 2032 16.50 11.00 2033 18.25 12.00 2034 20.00 13.00 2035 22.00 14.00 (3) Subsequent years (A) Calendar years 2036 through 2045 Not later than December 31, 2033, the Secretary shall promulgate regulations establishing performance standards for each of calendar years 2036 through 2045. (B) Subsequent extensions Except as provided in subparagraph (A), not later than the last day of the penultimate reporting period for which performance standards have been established under this paragraph, the Secretary shall promulgate regulations establishing performance standards for the 10-calendar-year period following the last calendar year for which performance standards previously were established. (C) Requirements The Secretary shall establish performance standards under this paragraph at levels reflecting the maximum achievable level of cost-effective energy efficiency potential, taking into account— (i) cost-effective energy savings achieved by leading retail electricity suppliers and retail natural gas suppliers; (ii) opportunities for new codes and standards savings; (iii) technology improvements