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
| Date | Valeur | Modifier , % |
|---|---|---|
| 2018 | 1 497 | 4 153,94 % |
| 2003 | 35 | 5,82 % |
| 2002 | 33 | -14,90 % |
| 2001 | 39 | -13,83 % |
| 2000 | 45 | -13,95 % |
| 1999 | 53 | 52,81 % |
| 1997 | 34 | 16,21 % |
| 1996 | 30 | 33,58 % |
| 1995 | 22 | -16,32 % |
| 1994 | 27 |