I don't know how many people understand that Dave Moulton is sort of a legend in bicycling. Even though some might consider him a bit weird with the temerity to be able to think for himself.

Dave's formula isn't meant to describe EXACTLY the size bike you need but if you're a newby, buying a bike based on his data will give you a bike close enough to the correct size that you can't go wrong.

His formula gives me a bike size 1 cm larger than I actually ride but his size is probably correct since I leaned in the LeMond era when everyone was riding bikes 2 or 3 cm smaller than they should have been.