A fascinating piece on how central banks came to settle on
2% as the preferred long-term inflation target:
http://www.nytimes.com/2014/12/21/upshot/of-kiwis-and-currencies-how-a-2-inflation-target-became-global-economic-gospel.html
http://www.nytimes.com/2014/12/21/upshot/of-kiwis-and-currencies-how-a-2-inflation-target-became-global-economic-gospel.html