Yesterday I noted the resilience of book sales in the UK, with a big surge in digital sales and a small decline only in physical sales. The figures were for total revenues. Looking at the Publishers Association yearbook (the absence of an apostrophe is theirs, not mine), there are some interesting unit price figures too.

In total, for physical books, average price increased by under 1% in 2011 and 2012, to reach £4.28. But big jumps in 2009 and 2010 mean the average price has climbed 17.2% since 2008. So, more or less matching general inflation in a flat economy, which is good going for items of leisure spending. However, in most categories, the price increase was rather lower, and in fact prices of non-fiction and reference books have declined over the five years. But school book prices have rocketed by 83.9% in four years, rising from £3.08 on average in 2008 to £5.66 in 2012.

Not surprisingly, unit sales have declined (by 13.3%), but at the price elasticity of demand implied by the figures, the profitability of the relevant books – is it all phonics textbooks? – must have been pleasing. Unit sales were down across the board, and by much more in most of the other categories (fiction, non-fiction, children’s, ELT, and by a similar 12.9% for academic books). There isn’t a long enough run of data to be sure but eyeballing the figures, it looks like roughly a unit price elasticity in the other categories.

However, the annual gives no figures on e-book prices. It would be fascinating to know what the pricing patterns, and profit margins, are.