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).
Helen
Helen is now well below its former popularity. All-time it's been given to 1,035,660 U.S. babies, the 754th most common name by sound today, peaking at 36,380 in 1918, with 780 in 2025.
By sound, Helen also includes the spellings Hellen.
Rising
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).