Show data table
| 1988 | 159.7% | 2001 | 85.5% | 2014 | 68.2% |
| 1989 | 190.3% | 2002 | 85.9% | 2015 | 71.4% |
| 1990 | 197.7% | 2003 | 80.4% | 2016 | 70.7% |
| 1991 | 180.5% | 2004 | 73.8% | 2017 | 69.1% |
| 1992 | 134.7% | 2005 | 66.1% | 2018 | 67.9% |
| 1993 | 122.2% | 2006 | 60% | 2019 | 69.4% |
| 1994 | 112.1% | 2007 | 58.2% | 2020 | 77.9% |
| 1995 | 102.4% | 2008 | 47.9% | 2021 | 79.9% |
| 1996 | 101.2% | 2009 | 51.8% | 2022 | 80.7% |
| 1997 | 94.7% | 2010 | 53.4% | 2023 | 81% |
| 1998 | 96.3% | 2011 | 56.1% | 2024 | 82.1% |
| 1999 | 98.7% | 2012 | 64% | 2025 | 82.8% |
| 2000 | 89.9% | 2013 | 68.8% | 2026 | 81.8% |
Show data table
| 1988 | 4.17B | 2001 | 6.2B | 2014 | 19.6B |
| 1989 | 5.13B | 2002 | 6.71B | 2015 | 21.5B |
| 1990 | 6.07B | 2003 | 6.66B | 2016 | 21.9B |
| 1991 | 5.94B | 2004 | 6.8B | 2017 | 22.4B |
| 1992 | 5.47B | 2005 | 6.79B | 2018 | 22.9B |
| 1993 | 5.32B | 2006 | 7.43B | 2019 | 24B |
| 1994 | 5.5B | 2007 | 8.18B | 2020 | 26.5B |
| 1995 | 5.42B | 2008 | 8.72B | 2021 | 28.8B |
| 1996 | 5.59B | 2009 | 10.1B | 2022 | 30.7B |
| 1997 | 5.48B | 2010 | 11.5B | 2023 | 32.3B |
| 1998 | 6.15B | 2011 | 13B | 2024 | 34.2B |
| 1999 | 6.5B | 2012 | 15.8B | 2025 | 36.2B |
| 2000 | 6.14B | 2013 | 18.5B | 2026 | 37.6B |