Show data table
| 1980 | 28.2% | 1996 | 37% | 2012 | 37.7% |
| 1981 | 28.9% | 1997 | 37.6% | 2013 | 38.7% |
| 1982 | 29.4% | 1998 | 38.4% | 2014 | 39% |
| 1983 | 31.2% | 1999 | 38.7% | 2015 | 38.4% |
| 1984 | 31.3% | 2000 | 38% | 2016 | 37.9% |
| 1985 | 33% | 2001 | 38% | 2017 | 38% |
| 1986 | 33.6% | 2002 | 38.3% | 2018 | 38.9% |
| 1987 | 35.3% | 2003 | 38% | 2019 | 39% |
| 1988 | 35.3% | 2004 | 38.7% | 2020 | 41.4% |
| 1989 | 37.1% | 2005 | 39.7% | 2021 | 42.8% |
| 1990 | 37.2% | 2006 | 40.5% | 2022 | 41.7% |
| 1991 | 38% | 2007 | 41.1% | 2023 | 42.1% |
| 1992 | 39.6% | 2008 | 36.8% | 2024 | 42.3% |
| 1993 | 39.4% | 2009 | 34.8% | 2025 | 42.2% |
| 1994 | 38.5% | 2010 | 36.4% | 2026 | 43.2% |
| 1995 | 37.3% | 2011 | 36.2% | | |
Show data table
| 1980 | 28B | 1996 | 181B | 2012 | 391B |
| 1981 | 32.8B | 1997 | 195B | 2013 | 397B |
| 1982 | 38.2B | 1998 | 213B | 2014 | 405B |
| 1983 | 46.3B | 1999 | 230B | 2015 | 418B |
| 1984 | 52.1B | 2000 | 246B | 2016 | 425B |
| 1985 | 61.2B | 2001 | 266B | 2017 | 444B |
| 1986 | 71.1B | 2002 | 287B | 2018 | 472B |
| 1987 | 83.2B | 2003 | 305B | 2019 | 489B |
| 1988 | 92.4B | 2004 | 333B | 2020 | 468B |
| 1989 | 109B | 2005 | 368B | 2021 | 529B |
| 1990 | 122B | 2006 | 407B | 2022 | 574B |
| 1991 | 137B | 2007 | 442B | 2023 | 630B |
| 1992 | 153B | 2008 | 409B | 2024 | 674B |
| 1993 | 159B | 2009 | 374B | 2025 | 711B |
| 1994 | 165B | 2010 | 392B | 2026 | 767B |
| 1995 | 172B | 2011 | 387B | | |
Show data table
| 1980 | 30.2% | 1996 | 42.9% | 2012 | 49.2% |
| 1981 | 31.3% | 1997 | 41.5% | 2013 | 46.2% |
| 1982 | 34.9% | 1998 | 41% | 2014 | 45.1% |
| 1983 | 35.9% | 1999 | 40% | 2015 | 43.7% |
| 1984 | 36.7% | 2000 | 39.1% | 2016 | 42.1% |
| 1985 | 39.8% | 2001 | 38.4% | 2017 | 41% |
| 1986 | 39.6% | 2002 | 38.6% | 2018 | 41.5% |
| 1987 | 38.5% | 2003 | 38.4% | 2019 | 42% |
| 1988 | 38.7% | 2004 | 38.8% | 2020 | 51.4% |
| 1989 | 40.1% | 2005 | 38.4% | 2021 | 49.5% |
| 1990 | 41.1% | 2006 | 38.4% | 2022 | 46.3% |
| 1991 | 42.6% | 2007 | 39.2% | 2023 | 45.4% |
| 1992 | 43.9% | 2008 | 41.3% | 2024 | 45.5% |
| 1993 | 46.3% | 2009 | 46.1% | 2025 | 44.7% |
| 1994 | 44.8% | 2010 | 45.8% | 2026 | 45.3% |
| 1995 | 44.1% | 2011 | 45.9% | | |
Show data table
| 1980 | 30B | 1996 | 210B | 2012 | 510B |
| 1981 | 35.5B | 1997 | 215B | 2013 | 473B |
| 1982 | 45.3B | 1998 | 228B | 2014 | 468B |
| 1983 | 53.3B | 1999 | 238B | 2015 | 475B |
| 1984 | 61.1B | 2000 | 253B | 2016 | 473B |
| 1985 | 73.8B | 2001 | 269B | 2017 | 480B |
| 1986 | 83.7B | 2002 | 290B | 2018 | 503B |
| 1987 | 90.9B | 2003 | 308B | 2019 | 527B |
| 1988 | 101B | 2004 | 334B | 2020 | 581B |
| 1989 | 118B | 2005 | 357B | 2021 | 611B |
| 1990 | 134B | 2006 | 386B | 2022 | 637B |
| 1991 | 153B | 2007 | 422B | 2023 | 680B |
| 1992 | 170B | 2008 | 460B | 2024 | 725B |
| 1993 | 187B | 2009 | 494B | 2025 | 753B |
| 1994 | 192B | 2010 | 494B | 2026 | 803B |
| 1995 | 203B | 2011 | 491B | | |