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).
Phoenix
Phoenix climbed for decades and has been a steadily popular name ever since. All-time it's been given to 40,635 U.S. babies, the 384th most common name by sound today, peaking at 2,650 in 2020, with 1,594 in 2025.
Phoenix has no common alternate spellings by sound.
Rising
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).