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MATERIALS, SUPPLIES, AND INVENTORIES
6 Months Ended
Jun. 30, 2020
Inventory Disclosure [Abstract]  
MATERIALS, SUPPLIES, AND INVENTORIES MATERIALS, SUPPLIES, AND INVENTORIES
Our inventory consisted of:
(in millions)June 30, 2020December 31, 2019
Materials and supplies$240.2  $234.2  
Natural gas in storage142.5  227.7  
Fossil fuel85.0  87.9  
Total$467.7  $549.8  

PGL and NSG price natural gas storage injections at the calendar year average of the costs of natural gas supply purchased. Withdrawals from storage are priced on the LIFO cost method. For interim periods, the difference between current projected replacement cost and the LIFO cost for quantities of natural gas temporarily withdrawn from storage is recorded as a temporary LIFO liquidation debit or credit. At June 30, 2020, we had a temporary LIFO liquidation debit of $12.6 million recorded within other current assets on our balance sheet. Due to seasonality requirements, PGL and NSG expect these interim reductions in LIFO layers to be replenished by year end.

Substantially all other materials and supplies, natural gas in storage, and fossil fuel inventories are recorded using the weighted-average cost method of accounting.