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).
Pedro
Pedro is now well below its former popularity. All-time it's been given to 94,582 U.S. babies, the 811th most common name by sound today, peaking at 1,711 in 2000, with 684 in 2025.
Pedro has no common alternate spellings by sound.
Rising
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).