I can't give you that stat but there are some great numbers showing a trend away from single-sport users at https://blog.strava.com/press/strava-releases-2019-y

I can't give you that stat but there are some great numbers showing a trend away from single-sport users at https://blog.strava.com/press/strava-releases-2019-year-in-sport-data-report/ https://blog.strava.com/press/strava-releases-2019-year-in-s... (download the zipped report at the top)