Year,Runoff (Gt/yr),Runoff uncertainty (Gt/yr) 2011,351.82,55.35 2012,526.77,55.59 2013,284.86,64.05 2014,326.17,55.59 2015,311.97,54.27 2016,452.47,72.84 2017,247.05,56.05 2018,295.98,53.41 2019,496.46,52.98 2020,277.14,53.43