New Orleans Saints : biggest year-to-year improvement/decline

Based on regular season win percentage:

                            Change in 
                              win %
Improvement: 1999 -> 2000     0.437   (0.188 -> 0.625)
Decline:     1979 -> 1980    -0.438   (0.500 -> 0.062)
Last Year:   2024 -> 2025     0.059   (0.294 -> 0.353)