Percentage signs in shops

I have an article in the TES Pro section tomorrow about shops and their use of percentages.

One of the things I wrote about is the use of signs saying ‘up to X% off’ which I feel is a bit dodgy really. However, I recently saw a Clarks shop where it went for the alternate approach ‘at least 30% off’ and I feel this is a fairer reflection. Of course, I understand it’s probably less powerful from a promotional point of view.

As luck would have it, next door was having the strangest % off sale I’ve seen. Look at the pic to see what it was.