Year current US$ 1995 11000000 1996 19000000 1997 21000000 1998 20000000 1999 28000000 2012 48000000 2013 41000000 2014 37000000 2015 29000000 2016 30000000 2017 23000000 2018 4000000 2019 11199999.8092651 2020 5500000