Original sentence: He inherited the Labour leadership at a time when the party was ascendant over the Conservatives in the opinion polls, since the Conservative government's reputation in monetary  policy was left in tatters by the Black Wednesday economic disaster of September 1992
Edited sentence: He inherited the Labour leadership at a time when the party was ascendant over the Conservatives in the opinion polls, since the Conservative government's reputation for monetary excellence record was left in tatters by the Black Wednesday economic disaster of September 1992