This water supply interannual variability is a normalized indicator of the variation in water supply between years. Estimations are given for the year 2013. Interannual variability is calculated as the standard deviation of annual total blue water divided by the mean of total blue water from 1950 to 2010. The indicator was created by the World Resources Institute (WRI) and ranges from 0-5, where 0 is lowest and 5 is highest. Values represent the "All-sector" indicator, and have been rounded to the nearest tenth by AQUASTAT.For more information, see WRI original analysis here: wri.org/publication/aqueduct-country-river-basin-rankings.Visit the FAO Aquastat website: http://www.fao.org/nr/water/aquastat/data/query/index.html?lang=en
