By Lars Mucklejohn American Express has sparked criticism for freezing pension payments for thousands of former British employees for the tenth year in a row. The US payment cards giant said in a letter to UK pension fund members on 22 March that it had considered the case for a discretionary increase in payouts and decided against it. Campaigners have said they have suffered a 30 per cent drop in the value of their pensions over the past decade when adjusted for inflation. During this period Amex has posted record profits from a boom in card spending and last year handed chief executive Steph…