The Economist has been publishing the Big Mac Index since 1986. In grad school I was studying Purchasing Power Parity and decided to use data from the Big Mac Index as part of my final paper. The problem was that the data available online only went back to the year 2000 and the years 1986 through 2000 were nowhere to be found.
I went to the University of Michigan library and spent about 14 hours looking through microfilm of old editions of The Economist until I found data for the years 1986 through 1999. This data is available in the spreadsheet that you can buy for $14 by clicking on the link on the right.
I used to have the actual images of the charts from the magazine issues available online but had to take them down for copyright reasons. In 1991, the Supreme Court ruled in Feist Publications, Inc., v. Rural Telephone Service Co., that information alone without a minimum of original creativity cannot be protected by copyright. Meaning, the actual prices of Big Mac’s cannot be copyrighted but the creative charts can be. So I took those down but kept the data up.
Starting in 2000, The Economist started publishing all the Big Mac Index data online and now they have an interactive tool as well with data going back to March of 2000.
If you’re looking to get as much Big Mac Index data, your best bet is to buy the spreadsheet to get the years 1986 through 1999 (which is not available on The Economist’s website) and then download the rest of the data from 2000 to present day straight from the Economist.