Consumer Price Index (and hence inflation) for the UK from 1850 to the present (monthly since June 1947).
Data
Key source files are:
We take these and just to a split out of annual from monthly and some tidying of the date format (see scripts/process.js).
Rant
Why is it always so complicated to get data. A quick search on the interwebs yields: http://www.ons.gov.uk/ons/rel/cpi/consumer-price-indices/october-2012/cpi-time-series-data.html
But this turns out to be so big that it does not open in a spreadsheet programme (if you take CSV). In addition all the series descriptions are mixed in at the bottom of the file so this is not machine processable!
Let's try instead to go for the series selector to try and break it down: http://www.ons.gov.uk/ons/datasets-and-tables/data-selector.html?dataset=mm23
But this is about 20 different series - which one do you want? Make an educated guess and repeat each time you're wrong!