Show data table
| 1981 | 41.9% | 1997 | 22.7% | 2013 | 31.2% |
| 1982 | 42.6% | 1998 | 23.9% | 2014 | 28.4% |
| 1983 | 42.8% | 1999 | 23.3% | 2015 | 26.1% |
| 1984 | 43.5% | 2000 | 28.7% | 2016 | 24.4% |
| 1985 | 43.9% | 2001 | 30.9% | 2017 | 28.5% |
| 1986 | 39.2% | 2002 | 30.8% | 2018 | 31.3% |
| 1987 | 39.1% | 2003 | 30.3% | 2019 | 31.8% |
| 1988 | 38% | 2004 | 30.2% | 2020 | 27.9% |
| 1989 | 40.9% | 2005 | 27.5% | 2021 | 32.8% |
| 1990 | 42.3% | 2006 | 33.8% | 2022 | 34.4% |
| 1991 | 39.7% | 2007 | 37.9% | 2023 | 34.6% |
| 1992 | 21% | 2008 | 33.1% | 2024 | 38.9% |
| 1993 | 25% | 2009 | 30.3% | 2025 | 36.3% |
| 1994 | 22.4% | 2010 | 32% | 2026 | 33% |
| 1995 | 21.6% | 2011 | 33.9% | | |
| 1996 | 21.7% | 2012 | 29.8% | | |
Show data table
| 1981 | 3.72B | 1997 | 212B | 2013 | 5.99T |
| 1982 | 4.18B | 1998 | 226B | 2014 | 6.32T |
| 1983 | 4.48B | 1999 | 252B | 2015 | 5.98T |
| 1984 | 4.68B | 2000 | 351B | 2016 | 5.84T |
| 1985 | 4.92B | 2001 | 429B | 2017 | 7.97T |
| 1986 | 4.36B | 2002 | 477B | 2018 | 10.19T |
| 1987 | 4.54B | 2003 | 554B | 2019 | 12.04T |
| 1988 | 4.68B | 2004 | 713B | 2020 | 10.44T |
| 1989 | 5.24B | 2005 | 838B | 2021 | 14.31T |
| 1990 | 5.29B | 2006 | 1.36T | 2022 | 18.52T |
| 1991 | 8.96B | 2007 | 1.88T | 2023 | 24.39T |
| 1992 | 11.8B | 2008 | 2.17T | 2024 | 31.37T |
| 1993 | 56.8B | 2009 | 1.99T | 2025 | 32.65T |
| 1994 | 85.7B | 2010 | 3.12T | 2026 | 34.16T |
| 1995 | 141B | 2011 | 4.47T | | |
| 1996 | 160B | 2012 | 4.98T | | |
Show data table
| 1981 | 45% | 1997 | 30.8% | 2013 | 32.2% |
| 1982 | 45.4% | 1998 | 36.2% | 2014 | 32.1% |
| 1983 | 45.9% | 1999 | 33.2% | 2015 | 31.2% |
| 1984 | 47% | 2000 | 34.5% | 2016 | 39.7% |
| 1985 | 47.8% | 2001 | 35.2% | 2017 | 32.2% |
| 1986 | 52% | 2002 | 35.5% | 2018 | 28.4% |
| 1987 | 52.8% | 2003 | 33.7% | 2019 | 30.8% |
| 1988 | 52.4% | 2004 | 31.8% | 2020 | 37.1% |
| 1989 | 52.7% | 2005 | 25.1% | 2021 | 35.9% |
| 1990 | 51.7% | 2006 | 26.2% | 2022 | 33.7% |
| 1991 | 46% | 2007 | 35.3% | 2023 | 31.9% |
| 1992 | 29.1% | 2008 | 37.6% | 2024 | 37.5% |
| 1993 | 38.3% | 2009 | 35.5% | 2025 | 34.6% |
| 1994 | 32.2% | 2010 | 31.6% | 2026 | 33.5% |
| 1995 | 26.6% | 2011 | 37.9% | | |
| 1996 | 28.6% | 2012 | 36.1% | | |
Show data table
| 1981 | 4B | 1997 | 288B | 2013 | 6.16T |
| 1982 | 4.45B | 1998 | 342B | 2014 | 7.14T |
| 1983 | 4.81B | 1999 | 359B | 2015 | 7.14T |
| 1984 | 5.05B | 2000 | 423B | 2016 | 9.5T |
| 1985 | 5.36B | 2001 | 490B | 2017 | 9.01T |
| 1986 | 5.79B | 2002 | 550B | 2018 | 9.26T |
| 1987 | 6.13B | 2003 | 616B | 2019 | 11.66T |
| 1988 | 6.45B | 2004 | 751B | 2020 | 13.9T |
| 1989 | 6.75B | 2005 | 764B | 2021 | 15.63T |
| 1990 | 6.47B | 2006 | 1.05T | 2022 | 18.16T |
| 1991 | 10.4B | 2007 | 1.75T | 2023 | 22.46T |
| 1992 | 16.3B | 2008 | 2.47T | 2024 | 30.25T |
| 1993 | 87.2B | 2009 | 2.34T | 2025 | 31.12T |
| 1994 | 123B | 2010 | 3.08T | 2026 | 34.72T |
| 1995 | 173B | 2011 | 5T | | |
| 1996 | 211B | 2012 | 6.02T | | |