That's a) self-reported and b) among cyclists who track their power i.e. have power-meter equipped bicycle and a head unit to record stats. Self-reporting infla

That's a) self-reported and b) among cyclists who track their power i.e. have power-meter equipped bicycle and a head unit to record stats. Self-reporting inflate the numbers by itself but, since most people don't actually have a power meter or/and don't bike, that group is made from quite fit people by selection.