books.google.com - This work documents the history of techniques that statisticians have used to manipulate economic, meteorological, biological, and physical data taken from observations recorded over time. The manipulation tools include percent change, index numbers, moving averages, and "first differences," i.e., subtracting...http://books.google.com/books/about/Statistical_Visions_in_Time.html?id=rlBUTabMo4wC&utm_source=gb-gplus-shareStatistical Visions in Time
