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).
Briggs
Briggs has been climbing in recent years. All-time it's been given to 9,476 U.S. babies, the 682nd most common name by sound today, peaking at 1,071 in 2024, with 930 in 2025.
Briggs has no common alternate spellings by sound.
Rising
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).