1980 (There were 20 number-one hits in 1980.)

1981 (There were 23 number-one hits in 1981, one of which had been #1 in 1980.)

1982 (There were 22 number-one hits in 1982, two of which had been #1 in 1981.)

1983 (There were 22 number-one hits in 1983, one of which had been #1 in 1982.)

1984 (There were 30 number-one hits in 1984, one of which had been #1 in 1983.)

1985 (There were 31 number-one hits in 1985, one of which had been #1 in 1984.)

1986 (There were 33 number-one hits in 1986.)

1987 (There were 35 number-one hits in 1987, one of which had been #1 in 1986.)

1988 (There were 39 number-one hits in 1988.)

1989 (There were 36 number-one hits in 1989.)

1990 (There were 34 number-one hits in 1990.)

1991 (There were 31 number-one hits in 1991, one of which had been #1 in 1990.)

1992 (There were 25 number-one hits in 1992, one of which had been #1 in 1991.)

1993 (There were 16 number-one hits in 1993, one of which had been #1 in 1992.)

1994 (There were 20 number-one hits in 1994, one of which had been #1 in 1993.)

1995 (There were 18 number-one hits in 1995)

1996 (There were 19 number-one hits in 1996, one of which had been #1 in 1995.)

1997 (There were 22 number-one hits in 1997, one of which had been #1 in 1996.)

1998 (There were 20 number-one hits in 1998.)

1999 (There were 22 number-one hits of 1999.)

2000 (There were 16 number-one hits in 2000.)

2001 (There were 21 number-one hits in 2001, one of which was a #1 in 2000.)

2002 (There were 19 number-one hits in 2002.)

2003 (There were 16 number-one hits in 2003.)

2004 (There were 18 number-one hits in 2004, one of which was a #1 in 2003.)

2005 (There were 14 number-one hits in 2005.)

2006 (There were 17 number-one hits in 2006, one of which was a #1 in 2005.)

2007 (There were 17 number-one hits in 2007, one of which was a #1 in 2006.)

2008 (There have been 9 number-one hits in 2008, one of which was a #1 in 2007.)