Year SPI (scale 0-100) 2005 39.825 2006 40.3625 2007 40.1375 2008 40.80625 2009 40.66875 2010 38.225 2011 37.51875 2012 37.51875 2013 36.1125 2014 34.04375 2015 35.4 2016 36.65 2017 41.3 2018 41.25 2019 43.09375 2020 50.675 2021 51.60625 2022 51.60625