My guess is that people get confused (reasonably so) when a female baby's name got mistakenly entered in the male column. These do sometimes show up as daft little bumps in the statistics.
There was one case of a man who grew up to be Lord
Anne Somebody 'because'
Queen Anne was his godmother, though it seems ludicrously snobbish. But in the absence outside Narnia of a
Queen Susan, I'm betting on the transcription error.