12 hour lag! Why?

 
I need help with a small piece of code that calculates the moving average of the Williams Percent Range indicator.

Here is the code:

         ArrayResize(WPRArray, WPR_MAPeriod);

         for (int j = 0; j < WPR_MAPeriod; j++)
         {
            WPRArray[j] = iWPR(symbol, WPR_Timeframe, WPR_Period, j);
         }
         double WPR_Average = iMAOnArray(WPRArray, 0, WPR_MAPeriod, 0, WPR_MAMethod, 0);
         
         WPR = DoubleToString(WPR_Average, 0);

It gives different values on the indicator on the chart and the value in the variable calculated for WPR, e.g.
Here the value on the indicator is -52,4541 where the value in the Variable WPR = -73 (rounded off)



And here is another example:
Value of the indicator = -63.5457 but the variable has the value -41(rounded off)

I have researched the issue and found that there is a 12 hour difference where the value in the variable lags the value of the indicator. 

Here is a chart over 20 hours of the values of the indi and the var to illustrate:


 


 

Can anybody just look at the 5 lines of code and tell me if it is correct or not?

I need to discover why there is this 12 hour lag between the value in the moving avrage indicator and the value held in the WPR variable.

 
Is there nobody that can help me with this problem?
 
From what I see and understand, you are doing it reverse. Could that be?

Try maybe using ArraySetAsSeries
Reason: