One of the AIL macros

[Vitandus]

/cleartarget [mod:alt]
/ins
/run local t,c,u=0,0,UnitExists("target") and "target" or "player" for i =1,18 do if i~=4 then local k=GetInventoryItemLink(u,i) if k then local _,_,_,l=GetItemInfo(k) t=t+l c=c+1 end end end if c>0 then print(t/c) end