Exchange Rate Mechanism Mr. Boyes To ask the Chancellor of the Exchequer at what level of divergence between United Kingdom inflation and the European average he assesses it would be appropriate for the pound sterling to enter the exchange rate mechanism. Mr. Ryderz I refer the hon. Member to my right hon. Friend the Chancellor of the Exchequer's evidence to the Treasury and Civil Service Select Committee on the 1990 Budget—questions 304 to 307.