Tabella dei dati
| 1985 | 70,9% | 1999 | 25,9% | 2013 | 43,9% |
| 1986 | 46,5% | 2000 | 44,4% | 2014 | 35,3% |
| 1987 | 33,7% | 2001 | 38,1% | 2015 | 25,6% |
| 1988 | 33,5% | 2002 | 36,8% | 2016 | 23,1% |
| 1989 | 31,5% | 2003 | 38,9% | 2017 | 22,7% |
| 1990 | 30,3% | 2004 | 41,7% | 2018 | 30% |
| 1991 | 29,6% | 2005 | 45,1% | 2019 | 28% |
| 1992 | 25,8% | 2006 | 47,8% | 2020 | 16,6% |
| 1993 | 25,2% | 2007 | 32,4% | 2021 | 21,7% |
| 1994 | 24,5% | 2008 | 63,3% | 2022 | 25,9% |
| 1995 | 24,2% | 2009 | 38,4% | 2023 | 21,5% |
| 1996 | 28,2% | 2010 | 36,8% | 2024 | 17,4% |
| 1997 | 27,2% | 2011 | 51,5% | 2025 | 16,5% |
| 1998 | 21,4% | 2012 | 50,7% | 2026 | 18,4% |
Tabella dei dati
| 1980 | 6,27 mld | 1996 | 2,86 mld | 2012 | 12,1 mld |
| 1981 | 8,46 mld | 1997 | 2,84 mld | 2013 | 9,93 mld |
| 1982 | 7,87 mld | 1998 | 1,92 mld | 2014 | 7,64 mld |
| 1983 | 7,75 mld | 1999 | 2,54 mld | 2015 | 4,55 mld |
| 1984 | 7,35 mld | 2000 | 5,08 mld | 2016 | 3,64 mld |
| 1985 | 7,53 mld | 2001 | 4,23 mld | 2017 | 3,81 mld |
| 1986 | 3,33 mld | 2002 | 4,27 mld | 2018 | 5,49 mld |
| 1987 | 2,75 mld | 2003 | 4,93 mld | 2019 | 5,14 mld |
| 1988 | 2,49 mld | 2004 | 6,15 mld | 2020 | 2,75 mld |
| 1989 | 2,53 mld | 2005 | 7,92 mld | 2021 | 4,09 mld |
| 1990 | 2,71 mld | 2006 | 9,65 mld | 2022 | 5,95 mld |
| 1991 | 2,69 mld | 2007 | 6,64 mld | 2023 | 4,36 mld |
| 1992 | 2,33 mld | 2008 | 14,3 mld | 2024 | 3,57 mld |
| 1993 | 2,27 mld | 2009 | 6,65 mld | 2025 | 3,45 mld |
| 1994 | 2,25 mld | 2010 | 6,87 mld | 2026 | 4 mld |
| 1995 | 2,45 mld | 2011 | 12 mld | | |
Tabella dei dati
| 1985 | 40,6% | 1999 | 44,1% | 2013 | 33,4% |
| 1986 | 40% | 2000 | 37,5% | 2014 | 34% |
| 1987 | 30,3% | 2001 | 35,5% | 2015 | 37% |
| 1988 | 36,6% | 2002 | 41,4% | 2016 | 39,8% |
| 1989 | 36,2% | 2003 | 30,9% | 2017 | 36,6% |
| 1990 | 32% | 2004 | 33,2% | 2018 | 32,9% |
| 1991 | 30,6% | 2005 | 29,1% | 2019 | 32,1% |
| 1992 | 34,1% | 2006 | 28% | 2020 | 32,8% |
| 1993 | 38% | 2007 | 29,3% | 2021 | 30,1% |
| 1994 | 47,1% | 2008 | 27,2% | 2022 | 26,1% |
| 1995 | 44% | 2009 | 34,8% | 2023 | 30,1% |
| 1996 | 36,9% | 2010 | 25,5% | 2024 | 30,3% |
| 1997 | 39% | 2011 | 29,9% | 2025 | 29,9% |
| 1998 | 45,4% | 2012 | 31,1% | 2026 | 29,1% |
Tabella dei dati
| 1980 | 1,14 mld | 1996 | 3,74 mld | 2012 | 7,41 mld |
| 1981 | 1,38 mld | 1997 | 4,08 mld | 2013 | 7,57 mld |
| 1982 | 2,17 mld | 1998 | 4,07 mld | 2014 | 7,37 mld |
| 1983 | 5,63 mld | 1999 | 4,32 mld | 2015 | 6,58 mld |
| 1984 | 4,14 mld | 2000 | 4,3 mld | 2016 | 6,27 mld |
| 1985 | 4,32 mld | 2001 | 3,95 mld | 2017 | 6,12 mld |
| 1986 | 2,87 mld | 2002 | 4,8 mld | 2018 | 6,02 mld |
| 1987 | 2,47 mld | 2003 | 3,91 mld | 2019 | 5,91 mld |
| 1988 | 2,71 mld | 2004 | 4,89 mld | 2020 | 5,44 mld |
| 1989 | 2,9 mld | 2005 | 5,11 mld | 2021 | 5,66 mld |
| 1990 | 2,85 mld | 2006 | 5,65 mld | 2022 | 6,01 mld |
| 1991 | 2,78 mld | 2007 | 6 mld | 2023 | 6,11 mld |
| 1992 | 3,07 mld | 2008 | 6,14 mld | 2024 | 6,21 mld |
| 1993 | 3,43 mld | 2009 | 6,03 mld | 2025 | 6,24 mld |
| 1994 | 4,31 mld | 2010 | 4,76 mld | 2026 | 6,34 mld |
| 1995 | 4,46 mld | 2011 | 6,97 mld | | |