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).
Dennis
Dennis is now well below its former popularity. All-time it's been given to 645,298 U.S. babies, the 1,033rd most common name by sound today, peaking at 25,230 in 1952, with 482 in 2025.
By sound, Dennis also includes the spellings Denis.
Rising
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).