데이터 표
| 1981 | 27.1억 | 1997 | 12.1억 | 2013 | 37.8억 |
| 1982 | 27.6억 | 1998 | 7.52억 | 2014 | 52.5억 |
| 1983 | 25.3억 | 1999 | 15.5억 | 2015 | 21.6억 |
| 1984 | 29.2억 | 2000 | 30억 | 2016 | 14.7억 |
| 1985 | 31.6억 | 2001 | 19.5억 | 2017 | 19.8억 |
| 1986 | 19.9억 | 2002 | 17.6억 | 2018 | 9.4억 |
| 1987 | 22.7억 | 2003 | 24.8억 | 2019 | 8.94억 |
| 1988 | 22.5억 | 2004 | 28.8억 | 2020 | 5.14억 |
| 1989 | 21.5억 | 2005 | 40.3억 | 2021 | 15.6억 |
| 1990 | 23.6억 | 2006 | 52.3억 | 2022 | 32.6억 |
| 1991 | 24.7억 | 2007 | 48.3억 | 2023 | 19.4억 |
| 1992 | 18.1억 | 2008 | 69.4억 | 2024 | 22.3억 |
| 1993 | 12.3억 | 2009 | 39.8억 | 2025 | 21.9억 |
| 1994 | 15.9억 | 2010 | 50.2억 | 2026 | 24.4억 |
| 1995 | 11.5억 | 2011 | 64.3억 | | |
| 1996 | 13.5억 | 2012 | 56.8억 | | |
데이터 표
| 1985 | 65.4% | 1999 | 26.7% | 2013 | 20.9% |
| 1986 | 60.6% | 2000 | 45.1% | 2014 | 30.7% |
| 1987 | 58.5% | 2001 | 31.4% | 2015 | 16.7% |
| 1988 | 60.9% | 2002 | 27.1% | 2016 | 12.9% |
| 1989 | 52.4% | 2003 | 34.2% | 2017 | 16.4% |
| 1990 | 47.8% | 2004 | 33% | 2018 | 6.9% |
| 1991 | 46.9% | 2005 | 38.2% | 2019 | 6.6% |
| 1992 | 32.7% | 2006 | 41.1% | 2020 | 4.3% |
| 1993 | 21.9% | 2007 | 35.6% | 2021 | 11.1% |
| 1994 | 26.5% | 2008 | 43.5% | 2022 | 19.5% |
| 1995 | 16.1% | 2009 | 33.4% | 2023 | 12.9% |
| 1996 | 18.8% | 2010 | 36.6% | 2024 | 14.5% |
| 1997 | 17.2% | 2011 | 34.7% | 2025 | 13.7% |
| 1998 | 14% | 2012 | 29.8% | 2026 | 14.5% |