Client Expression causes Worksheet to display no data

Hi All,

We have a Worksheet which displays data most of the time but  does not show data for one sceanrio.

We have narrowed down the columns to a specific series which has client expression

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if(isnull(  user adj fcst qty),0,   ( user adj fcst qty +  System Adj Fcst Qty )   * unit_cost )

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Please advice how to make this more robust to support null columns--scenario where

1) user adj fcst qty   is null

2) System Adj Fcst Qty  is null

3) Unit_cost is null

Can you please provide me robust expression to incorporate all possibility of Null Scenarios.

Thanks for your help

rgds

Aqil