We moved from decimal to decimal this time - admittedly the change from non-decimal to decimal was a long while ago, but it's still good for complaint! Pity it wasn't the fives tables for you, but ours was worse - something like 1 £(punt) = €1.25, so we'd to get a quarter and add it on to figure that direction (forgotten which now!) - which was nothing compared to the reverse conversion. Good for the mental maths, I guess.