Sac dollar coin number

I have a question about the Sac dollor coin number. Why has every pic. on E-bay I have seen has a coin number of coin 6 for the 2003 D and P coins. should it not be 7 and 8 ? Someone please help me here.
U S Navy Retired 22 years - ENC(SW) Ret. - Travling Nuclear Maintanence Contractor - Working Indian Point Nuclear plant Buchanan New York

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Comments
9584 2000-P SAC $1 MS
99584 2000-P SAC $1Goodacre MS
9585 2000-D SAC $1 MS
99585 2000-D SAC $1Millennium MS
15000 2001-P SAC $1 MS
15001 2001-D SAC $1 MS
Frank
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those guys started some weird numbering system that goes something like this
account number - item and sub items
500 sandwiches
5001 onions
5002 tomatos
5003 green peppers
i'm on to something here but can't explain it totally. Notice in Steve27's example of listings the similarities of date/mm and coin number. I think it's related to being able to catalog a number and allow for variations in the future.
OR i'm wrong....
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