when i join two tables together and get the sum, i am getting the correct figure:

```
select 
    d.accn_id,
    cast(d.load_date as DATE) as LoadDate,
    cast (d.final_rpt_date as DATE) as FinalReportDate,
    sum(p.paid_amt) as SumPaidAmt

from
    accn_demographics d
join 
    accn_payments p
on 
    d.ACCN_ID=p.ACCN_ID
where 
    p.POSTED='y'
    and p.PMT_DATE between '20120501' and '20120531'

group by 
    d.accn_id,
    d.load_date,
    d.final_rpt_date

```

however after i join ANOTHER table accn\_payors:

```
select 
    d.accn_id,
    cast(d.load_date as DATE) as LoadDate,
    cast (d.final_rpt_date as DATE) as FinalReportDate,
    sum(p.paid_amt) as SumPaidAmt
    ,payors.PAYOR_ID
from
    accn_demographics d
join 
    accn_payments p
on 
    d.ACCN_ID=p.ACCN_ID
left join 
    accn_payors payors
on  
    payors.X_PAYOR_ID=p.X_PRICED_PAYOR_ID 
    and payors.ACCN_ID = p.ACCN_ID
where 
    p.POSTED='y'
    and p.PMT_DATE between '20120501' and '20120531'

group by 
    d.accn_id,
    d.load_date,
    d.final_rpt_date
    ,payors.PAYOR_ID

```

i am getting an overstatement of `sum(p.paid_amt)`

the question is how can i adjust my join so that i am not joining multiple times?