GS_raw = wS×(Shares/Reach) + wC×(Comments/Reach) + wK×(LinkClicks/Reach)
+ wSv×(Saves/Reach) + wE×(Reactions/Reach) + wI×(I_other/Reach) + wR×r
GS = GS_raw x Scale (default 1000)
GP_post = round( (GS / Scale) x Reach x g_aud ) g_aud: audience weighting adjusted by Non-followers % (default +/-10%)