Buffalo Bills : biggest year-to-year improvement/decline

Based on regular season win percentage:

                            Change in 
                              win %
Improvement: 1972 -> 1973     0.322   (0.321 -> 0.643)
Decline:     1975 -> 1976    -0.428   (0.571 -> 0.143)
Last Year:   2024 -> 2025    -0.059   (0.765 -> 0.706)