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).
Laura was more common in the past and has since settled at a lower, steady level. All-time it's been given to 856,874 U.S. babies, the 730th most common name by sound today, peaking at 20,586 in 1964, with 863 in 2025.
By sound, Laura also includes the spellings Lora.