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).
Dalton
Dalton is now well below its former popularity. All-time it's been given to 86,142 U.S. babies, the 899th most common name by sound today, peaking at 4,590 in 1998, with 705 in 2025.
Dalton has no common alternate spellings by sound.
Rising
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).