Payment vs Zip and diagnosis

SELECT AVG([ Net_Paid ]) Payment, [ Employee_ZIP_Code ] ZIP,[SHORT DESCRIPTION]
FROM [SiemensHealthPlanData].[dbo].[unitedHealth],
[SiemensHealthPlanData].[dbo].[procedureCodeICD9]
where [ Primary_Diagnosis ] = [PROCEDURE CODE]
group by [ Employee_ZIP_Code ],[SHORT DESCRIPTION]



SELECT AVG([ Net_Paid ]) Payment,[SHORT DESCRIPTION]
FROM [SiemensHealthPlanData].[dbo].[unitedHealth],
[SiemensHealthPlanData].[dbo].[procedureCodeICD9]
where [ Primary_Diagnosis ] = [PROCEDURE CODE]
group by [SHORT DESCRIPTION]