Annual Reports Title 2024 Annual Report 2023 Annual Report 2022 Annual Report 2021 Annual Report 2020 Annual Report Proxy Materials Filing date View Jun 03, 2024 View HTML 0000006845-24-000177.pdf 0000006845-24-000177.rtf 0000006845-24-000177.xls EX-101.SCH - XBRL TAXONOMY EXTENSION SCHEMA May 09, 2024 View HTML 0000006845-24-000147.pdf 0000006845-24-000147.rtf 0000006845-24-000147.xls EX-101.SCH - XBRL TAXONOMY EXTENSION SCHEMA May 09, 2024 View HTML 0000006845-24-000149.pdf 0000006845-24-000149.rtf 0000006845-24-000149.xls May 12, 2023 View HTML 0000006845-23-000011.pdf 0000006845-23-000011.rtf 0000006845-23-000011.xls EX-101.SCH - XBRL TAXONOMY EXTENSION SCHEMA May 12, 2023 View HTML 0000006845-23-000013.pdf 0000006845-23-000013.rtf 0000006845-23-000013.xls