[AccessD] Top Values Query

In the attached query I am attempting to get the top three dates for each PID in the dbo_DSS_Welltests table. I calculate I should be getting 3 records for each of 9 PIDs for a total of 27 records. I only get 7 records. 

SELECT TOP 3 dbo_DSS_Welltests.TestDate, dbo_DSS_Welltests.PID
FROM dbo_DSS_Welltests 
INNER JOIN ConfigMaster ON dbo_DSS_Welltests.PID = ConfigMaster.ChildPID
WHERE ((([Configmaster].[PID]) 
In ("PAT 225-10","PAT 225-8","PAT 225-11","PAT 225-3A")))
ORDER BY dbo_DSS_Welltests.TestDate DESC;

Chester Kaup
Engineering Technician
Kinder Morgan CO2 Company, LLP
Office (432) 688-3797
FAX (432) 688-3799

 
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