I am able to get a chart control to work.
I created a query ConsultationsChart:
SELECT Nz([Year],"None") AS YearCPT, Nz([ProvideName],"None") AS Provider, T_ProcedureCode.CPT, Sum(Nz([N],0)) AS SumOfN
FROM T_ProcedureCode LEFT JOIN T_CPT ON T_ProcedureCode.CPT = T_CPT.CPT
GROUP BY Nz([Year],"None"), Nz([ProvideName],"None"), T_ProcedureCode.CPT
HAVING (((T_ProcedureCode.CPT)<"99206"));
Then the RowSource for chart control:
SELECT CPT, SumOfN FROM [ConsultationsChart] WHERE [YearCPT]=[Year] AND [Provider]=[ProvideName];