Among the major currencies only the dollar had a worse week than sterling. It lost two thirds of a cent to the pound and two and a half cents to the euro as well as two and a quarter yen. The US economic data did it no great favours: investors were particularly disappointed by soft retail sales in April and by the slowdown of inflation from 2.4% to 2.2%. However, it was politics that held investors’ attention and perturbed them most. Almost every day saw a new bone of contention laid at the White House door, the most recent being the appointment of a special prosecutor to investigate the president.

Sterling was looking comfortable against the dollar, especially after some surprisingly strong UK retail sales figures on Thursday. But when the pound got above $1.30, its highest level in nearly a year, investors bottled out and sterling dropped back.