That makes off-the-peg solutions impossible.

ECONOMIST: AIDS

The condition to peg off-peak fares at RPI -1, or 1% below the retail price index measure of inflation, will be written into the contract for the next rail franchise.

BBC: Below-inflation Scottish off-peak rail fare pledge

In 1931, as the Austrian bank Creditanstalt collapsed, pulling down the banks of Germany, Czechoslovakia, Hungary and Poland, a run on the German currency forced it off the Gold Standard in May, then the British Labour government struggled to maintain its currency peg - imposing austerity onto its own voters as the price.

BBC: Euro: A 'loose cannon on the deck of the world'?