Figures in constant (2020) US$ are present according to calendar year, calculated on the assumption that, where financial years do not correspond to calendar years, spending is distributed evenly through the year
| التاريخ | Value | تغيير , % |
|---|---|---|
| 2021 | 28,398 | 4.02 % |
| 2020 | 27,301 | 4.89 % |
| 2019 | 26,029 | 2.71 % |
| 2018 | 25,342 | -2.39 % |
| 2017 | 25,962 | -0.18 % |
| 2016 | 26,008 | 9.50 % |
| 2015 | 23,751 | 10.23 % |
| 2014 | 21,546 | 8.53 % |
| 2013 | 19,852 | -0.87 % |
| 2012 | 20,026 | -3.50 % |
| 2011 | 20,754 | -1.39 % |
| 2010 | 21,045 |