Domestic sales of natural gas decreased by 55.4% in the three-month period ended March 31, 2022, from Ps. 22.4 billion in the three-month period ended March 31, 2021, to Ps. 10.0 billion in the three-month period ended March 31, 2022, mainly due to a 58.9% decrease in its average sales price.
Domestic sales of liquefied petroleum gas increased by 55.2% in the three-month period ended March 31, 2022, from Ps. 12.5 billion in the three-month period ended March 31, 2021, to Ps. 19.4 billion in the three-month period ended March 31, 2022, mainly as a result of an 46.1% increase in its average sales price.
Export Sales
Export sales increased by 68.4% in peso terms in the three-month period ended March 31, 2022 (with U.S. dollar-denominated export revenues translated to pesos at the exchange rate on the date of the corresponding export sale), from Ps. 149.0 billion in the three-month period ended March 31, 2021, to Ps. 250.9 billion in the three-month period ended March 31, 2022. This increase was mainly due to a 53.8% increase in the weighted average Mexican export crude oil price in the three-month period ended March 31, 2022, as compared to the three-month period ended March 31, 2021. From January 1 to March 31, 2021, the weighted average Mexican export crude oil price was U.S. $59.22 per barrel, compared to U.S. $91.08 per barrel in the same period of 2022. Export sales of Deer Park as of March 31, 2022 amounted Ps. 52.5 billion, which mainly related to petroleum distillates and gasolines.
Crude oil and condensate sales increased by 46.5%, from Ps. 96.7 billion in the three-month period ended March 31, 2021 to Ps. 141.7 billion in the three-month period ended March 31, 2022, and in U.S. dollar terms (actual invoiced amount in U.S. dollars) increased by 43.1%, from U.S. $5.1 billion in the three-month period ended March 31, 2021 to U.S. $7.3 billion in the three-month period ended March 31, 2022. The weighted average price per barrel of crude oil exports in the three-month period ended March 31, 2022 was U.S. $91.08, or 53.8% higher than the weighted average price of U.S. $59.22 in the three-month period ended March 31, 2021.
Export sales of petroleum products, including products derived from natural gas and natural gas liquids, increased by 98.5%, from Ps. 13.8 billion in the three-month period ended March 31, 2021, to Ps. 27.4 billion in the three-month period ended March 31, 2022, primarily due to a 45.7% increase in the sales prices of fuel oil.
For the three-month period ended March 31, 2022, the average exchange rate of the U.S. dollar against the Mexican peso was Ps. 20.5229 = U.S. $1.00, as compared to Ps. 20.3190 = U.S. $1.00 during the same period of 2021, representing a depreciation of the peso against the U.S. dollar by Ps. 0.2039 (or 1.0%), which had a favorable effect on our export sales of Ps. 3.9 billion in the three-month period ended March 31, 2022.
Reversal of Impairment of Wells, Pipelines, Properties, Plant and Equipment, Net
Net reversal of impairment of wells, pipelines, properties, plant and equipment decreased by Ps. 30.3 billion in the three-month period ended March 31, 2022 as compared to the three-month period ended March 31, 2021, from a net reversal of impairment of Ps. 46.6 billion in the three-month period ended March 31, 2021, to a net reversal of impairment of Ps. 16.3 billion in the three-month period of 2022. This net reversal of impairment was primarily due to a net reversal of impairment of Ps. 11.5 billion in the cash generating units (CGUs) of Pemex Exploration and Production, primarily due to a higher increase in crude oil prices in the first three-month period ended March 31, 2021, as compared to the increase in prices for the same period of 2022; and a net reversal of impairment of Ps. 4.8 billion in the cash generating units (CGUs) of Pemex Industrial Transformation, due to an increase in refined products prices.
Cost of Sales
Cost of sales increased by 48.9%, or Ps. 106.9 billion in the three-month period ended March 31, 2022, from Ps. 218.5 billion in the three-month period ended March 31, 2021 to Ps. 325.4 billion in the three-month period ended March 31, 2022. This increase was mainly due to (1) a Ps. 44.3 billion increase in import purchases, primarily of Magna gasoline and liquefied petroleum gas, due to an increase in the purchase price of these products and (2) a Ps. 15.5 billion increase in exploration and extraction taxes and duties, mainly due to the recovery of hydrocarbon prices from lows reached during the initial months of the COVID-19 pandemic.
Administrative expenses and Distribution, Transportation and Sale expenses
Administrative expenses and Distribution, Transportation and Sale expenses increased by 12.8%, from Ps. 36.6 billion for the three-month period ended March 31, 2021 to Ps. 41.3 billion for the three-month period ended March 31, 2022, mainly due to an increase in net periodic cost of employee benefits.
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