Regular season
| Year | Team | Games | Att | Cmp | Cmp% | Pass Yds | Pass TD | INT | Sacks | Y/A | Rating |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1978 | SF | 12 | 302 | 137 | 45.4 | 1570 | 8 | 22 | 17 | 5.2 | 40.0 |
| 1979 | SF | 16 | 578 | 347 | 60.0 | 3652 | 17 | 21 | 17 | 6.3 | 73.1 |
| 1980 | SF | 11 | 321 | 186 | 57.9 | 1998 | 12 | 17 | 14 | 6.2 | 66.7 |
| 1981 | DEN | 14 | 108 | 64 | 59.3 | 797 | 6 | 6 | 7 | 7.4 | 77.6 |
| 1982 | DEN | 9 | 223 | 131 | 58.7 | 1405 | 7 | 11 | 16 | 6.3 | 67.2 |
| 1983 | DEN | 10 | 215 | 119 | 55.3 | 1617 | 9 | 7 | 25 | 7.5 | 79.9 |
| 1984 | TB | 16 | 509 | 308 | 60.5 | 3554 | 19 | 18 | 35 | 7.0 | 79.3 |
| 1985 | TB | 11 | 370 | 197 | 53.2 | 2488 | 19 | 18 | 19 | 6.7 | 71.3 |
| 1986 | TB | 16 | 96 | 50 | 52.1 | 610 | 5 | 12 | 9 | 6.4 | 49.7 |
| 1987 | TB | 12 | 275 | 159 | 57.8 | 1891 | 14 | 7 | 20 | 6.9 | 85.3 |
| 1988 | KC | 13 | 414 | 224 | 54.1 | 2935 | 16 | 16 | 30 | 7.1 | 73.5 |
| 1989 | KC | 12 | 324 | 196 | 60.5 | 2529 | 11 | 16 | 14 | 7.8 | 75.8 |
| 1990 | KC | 16 | 444 | 258 | 58.1 | 3444 | 23 | 4 | 22 | 7.8 | 96.3 |
| 1991 | KC | 16 | 434 | 256 | 59.0 | 2965 | 17 | 14 | 19 | 6.8 | 79.3 |
| 1992 | TB | 6 | 125 | 76 | 60.8 | 710 | 3 | 4 | 8 | 5.7 | 71.1 |
| 1993 | TB | 8 | 227 | 136 | 59.9 | 1707 | 7 | 10 | 18 | 7.5 | 75.3 |
| 1998 | ATL | 8 | 59 | 30 | 50.8 | 369 | 3 | 1 | 6 | 6.3 | 80.4 |