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GB – ConsumptionOnBillLastBillZero 
Checks that Checks the value of consumption is still zero if there was zero consumption on the previous billon the previous bill is zero, then checks the value of this bill.
If there is consumption (not necessarily cost), the Validator will fail.
Validator Set Up
Variables
There are no Variables for this Validator
Failure Prompt
Consumption on bill when last bill has zero consumption: FAILED - name of the Validator
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