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In SAS OnlineDoc® for SAS®9 and later, the SAS/ETS® User's Guide 
contains incorrect weight values for the MOVAVE transformation operator. 
In the "Table of Transformation Operators", the following formula for 
the MOVAVE(w1...wn) operator is given: 
 
    n                         n 
  (Sum (w_j * x_(t-j+1) ) / (Sum (w_j))) 
   j=1                       j=1 
 
For a 5-term weighted moving average in which MOVAVE(w1 w2 w3 w4 w5) is 
specified in the CONVERT statement, the documentation implies that the 
calculation for observation 10 of the data would be as follows: 
 
   ma_10 = (w1*x_10 + w2*x_9 + w3*x_8 + w4*x_7 + w5*x_6) / 1 
 
However, PROC EXPAND performs the calculation as follows: 
 
   ma_10 = (w1*x_6 + w2*x_7 + w3*x_8 + w4*x_9 + w5*x_10) / 1 
 
NOTE:  The denominator in the preceding formulas is 1 because the 
weights are normalized to sum to 1. 
 
The computational formula for the MOVAVE(w1...wn) transformation 
operator should be documented as follows: 
 
    n                         n 
  (Sum (w_j * x_(t-n+j) ) / (Sum (w_j))) 
   j=1                       j=1 
 
where n is the number of weights specified. 
 
Therefore, when you specify weights for the MOVAVE (w1...wn) 
transformation operator, the last weight "wn" should match the current 
observation, and the first weight "w1" should match the lag "n" 

observation. 

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