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).
Dale is now well below its former popularity. All-time it's been given to 303,363 U.S. babies, the 1,998th most common name by sound today, peaking at 9,175 in 1958, with 134 in 2025.
By sound, Dale also includes the spellings Dayle.
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).