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).
Melanie is down from its peak but still widely used. All-time it's been given to 296,471 U.S. babies, the 240th most common name by sound today, peaking at 6,690 in 1972, with 3,112 in 2025.
By sound, Melanie also includes the spellings Melany, Melani, Melonie, Melony.
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).