This warning occurs when third sub-attribute of an attribute is mandatory and is not specified. %s - attribute name.
Provide the third attribute.
Example
[#Report: Balance Sheet]
Collection: My Collection
[Collection: My Collection]
Source Collection : Default
Walk : Ledger Entries
Compute Var : vLedgerName : String : $LedgerName
By : LedgerName : ##vLedgerName
Aggr Compute : Amount : Sum
In the example, the Aggr Compute attribute of MyCollection does not have third mandatory attribute. Hence the warning, warning T0014: The mandatory third value of 'Aggr Method' is not given appears.
The code is corrected by providing the third attribute.
[#Report: Balance Sheet]
Collection: My Collection
[Collection: My Collection]
Source Collection : Default
Walk : Ledger Entries
Compute Var : vLedgerName : String : $LedgerName
By : LedgerName : ##vLedgerName
Aggr Compute : Amount : Sum : $Amount
