2.1.877 Part 1 Section 126.96.36.199, AVEDEV
a. The standard specifies the mathematical formula for AVEDEV to be C(n,k) = P(k,n)/k!=n!/(k!(n-k)!).
Office uses the mathematical formula: (1/n) ∑|x - x-bar| and maps n to the size of the data set, x to a value from the data set, and x-bar as the AVERAGE(argument-list).