Property ‘ELEMENT_DATA’ is used before its initialization

Error: src/app/get-api/get-api.component.ts:16:55 – error TS2729: Property ‘ELEMENT_DATA’ is used before its initialization.

16   dataSource = new MatTableDataSource<ApiReport>(this.ELEMENT_DATA);

                                                      ~~~~~~~~~~~~

  src/app/get-api/get-api.component.ts:14:3
    14   ELEMENT_DATA: ApiReport[];
         ~~~~~~~~~~~~
    'ELEMENT_DATA' is declared here.

Source: Angular Questions