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).
Darius
Darius is now well below its former popularity. All-time it's been given to 54,278 U.S. babies, the 1,287th most common name by sound today, peaking at 2,200 in 1994, with 322 in 2025.
Darius has no common alternate spellings by sound. Spellings sometimes heard the same way: Darrius.
Rising
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).