What do you mean by "sum of D6"? D6 is a single cell...there is nothing to sum.
If you want D370 to always show the same value as D6, put this in D370:
If you want to put =SUM(D6+G6+J6) in D6, you are out of luck. That will produce a Circular Reference error.
Imagine what would happen each time the worksheet calculated. Excel would add the values to D6 and then try to add those values to the new value in D6 and then try to add those values to the new value in D6 and repeat this over and over and over again non-stop.
You have 2 choices:
1 - Use any cell other than D6 for =SUM(D6+G6+J6)
2 - Use VBA (a macro) which is not restricted by "circular references" because it can evaluate the formula itself and then just put the result in the cell:
Range("D6") = WorksheetFunction.Sum(Range("D6,G6,J6"))
In other words, VBA will perfrom the SUM operation within VBA and then write the value into the cell. If you look in D6, all you will see is the result, not a formula.
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