Prices ending in 9 sell, on average, 24% better than the nearest rounded price point. This is usually attributed to the way our brains subconsciously understand numbers, using the left-hand digit to set the reference for the rest of the number.

By ending a number in 9, instead of 0 (say £39 instead of £40), we’re encouraging the brain to subconsciously associate the price with the lower reference point (£30, instead of £40) – and making the decision to buy a little bit easier.