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).
Hendrix
Hendrix has been climbing in recent years. All-time it's been given to 14,396 U.S. babies, the 595th most common name by sound today, peaking at 1,355 in 2021, with 975 in 2025.
Hendrix has no common alternate spellings by sound.
Rising
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).