How to read the band →
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).
Stacy
Stacy is now well below its former popularity. All-time it's been given to 412,856 U.S. babies, the 1,557th most common name by sound today, peaking at 21,909 in 1971, with 206 in 2025.
By sound, Stacy also includes the spellings Stacey, Stacie, Staci.
Rising
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).