Book distribution trends by year.
| 9,464,328 |
| 13,756,540 |
| 7 |
| 2021 |
| 7 | 2020 | 5,693,284 | 9,344,494 | 10 | 2020 |
| 8 | 2019 | 8,300,715 | 13,368,369 | 13 | 2019 |
| 9 | 2018 | 8,771,166 | 14,360,840 | 13 | 2018 |
| 10 | 2017 | 8,349,994 | 11,911,038 | 13 | 2017 |
| 11 | 2016 | 8,373,085 | 12,337,122 | 13 | 2016 |
| 12 | 2015 | 9,334,920 | 18,299,361 | 13 | 2015 |
| 13 | 2014 | 8,943,906 | 17,077,634 | 13 | 2014 |
| 14 | 2013 | 7,901,167 | 11,235,671 | 13 | 2013 |
| 15 | 2012 | 7,742,496 | 10,938,858 | 13 | 2012 |
| 16 | 2011 | 7,112,223 | 9,803,360 | 13 | 2011 |
| 17 | 2010 | 6,419,904 | 5,945,316 | 1 | 2010 |
| 18 | 2009 | 6,048,015 | 5,456,334 | 1 | 2009 |
| 19 | 2008 | 5,437,285 | 4,804,937 | 1 | 2008 |
| 20 | 2007 | 5,365,006 | 4,827,934 | 1 | 2007 |
| 21 | 2006 | 4,507,076 | 4,196,238 | 1 | 2006 |
| 22 | 2005 | 4,415,088 | 3,958,797 | 1 | 2005 |
| 23 | 2004 | 4,326,865 | 3,563,826 | 1 | 2004 |
| 24 | 2003 | 3,632,185 | 3,063,071 | 1 | 2003 |
| 25 | 2002 | 2,837,863 | 2,474,038 | 1 | 2002 |
| 26 | 2001 | 2,922,505 | 2,379,825 | 1 | 2001 |
| 27 | 2000 | 2,854,804 | 2,293,992 | 1 | 2000 |
| 28 | 1999 | 3,206,638 | 2,534,463 | 1 | 1999 |
| 29 | 1998 | 4,834,860 | 4,025,515 | 1 | 1998 |
| 30 | 1997 | 6,577,565 | 4,805,313 | 1 | 1997 |
| 31 | 1996 | 9,207,432 | 6,604,950 | 1 | 1996 |
| 32 | 1995 | 8,976,314 | 6,383,361 | 1 | 1995 |
| 33 | 1994 | 9,980,877 | 7,020,817 | 1 | 1994 |
| 34 | 1993 | 9,545,520 | 7,515,183 | 1 | 1993 |
| 35 | 1992 | 9,137,506 | 7,463,596 | 1 | 1992 |
| 36 | 1991 | 8,469,481 | 6,598,877 | 1 | 1991 |
| 37 | 1990 | 7,054,895 | 4,539,184 | 1 | 1990 |
| 38 | 1989 | 5,598,513 | 3,234,723 | 1 | 1989 |
| 39 | 1988 | 1,102,353 | 598,638 | 1 | 1988 |
| 40 | 1987 | 1,339,241 | 913,375 | 1 | 1987 |
| 41 | 1986 | 3,794,432 | 1,773,270 | 1 | 1986 |
| 42 | 1985 | 10,304,658 | 5,236,235 | 1 | 1985 |
| 43 | 1984 | 9,896,828 | 5,514,404 | 1 | 1984 |
| 44 | 1983 | 13,109,363 | 6,186,552 | 1 | 1983 |
| 45 | 1982 | 8,291,658 | 4,140,028 | 1 | 1982 |
| 46 | 1981 | 6,336,832 | 2,425,548 | 1 | 1981 |
| 47 | 1980 | 6,837,996 | 2,337,900 | 1 | 1980 |
| 48 | 1979 | 18,348,541 | 5,805,393 | 1 | 1979 |