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000110935710-QMarch 31, 2021false2021Q1December 31977,175,23500011681650000022606127,021,3800000078100170,478,50700000094661,0000001135971000007973210000000278791,00000000081928,546,017PA10 South Dearborn StreetP.O. Box 805379ChicagoIL60680-5379(800)483-3220PA300 Exelon WayKennett SquarePA19348-2473(610)765-5959IL440 South LaSalle StreetChicagoIL60605-1028(312)394-4321PAP.O. 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