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To demonstrate the efficiency of using VAR statements, perform the following steps:

1. Create the following measures:

Sum 6 =
 IF(
 SUMX('R11_Table','R11_Table'[Value]) = 0,
 0,
 SUMX('R11_Table','R11_Table'[Value])
 )
 
 Sum 7 =
 VAR __Sum = SUMX('R11_Table','R11_Table'[Value])
 RETURN
 IF(__Sum = 0,
 0,
 SUMX('R11_Table','R11_Table'[Value])
 )

2. Create a Card visualization and place the Sum 6 measure in the Fields area of the visualization.
3. Create a second Card visualization and place the Sum 7 measure in the Fields area of the visualization.
4. Analyze the Card visualizations for Sum 6 and Sum 7 using Performance Analyzer.

You should see that Sum 7 consistently takes a shorter amount of time to complete than Sum 6. This is because Sum 6 performs the SUMX calculation twice, while Sum 7 only performs the SUMX calculation once.