Solid line = floor (spellings that unambiguously belong to the group). Shaded band up to the dashed edge = ceiling (the most it could reach if every ambiguous spelling counted here).
Melody has been climbing in recent years. All-time it's been given to 125,586 U.S. babies, the 263rd most common name by sound today, peaking at 3,189 in 2025, with 3,189 in 2025.
By sound, Melody also includes the spellings Melodie.
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).