[RESOLVED] Sql Server 2000 Function, set variable to column value

[JuggaloBrotha]

I've got a table that holds a rate value and an effective date:

ID | EffectiveDate | AdminCost
1  | 2000-01-01    | 200.00
2  | 2010-01-01    | 225.00
3  | 2012-01-01    | 250.00

I'm trying to make a Function that will return the value of AdminCost column for a single record, I'm able to get that record with this query just fine:

Select Top 1 AdminCost, max(ID)
from tbl_pwe_tcr_DefaultAmounts
where EffectiveDate < @EntryDate
Group By ID, AdminCost

Which means when the date passed in is between "Jan 1 2010" and "Jan 1 2012" it returns the '225.00' and I'm trying to set that value to a function variable to return it to the Stored Proc that calls this, but when I try set it to a variable, I get an error, here's the function I'm trying to create:

Create Function [dbo].[fn_GetAdminFee] (@EntryDate DateTime)
Returns numeric(6, 2)
As
Begin
	Declare @Amount numeric(6, 2)

	Select Top 1 @Amount = AdminCost, max(ID)
	from tbl_pwe_tcr_DefaultAmounts
	where EffectiveDate < @EntryDate
	Group By ID, AdminCost

	Return @Amount
End

The error I'm getting is:

A SELECT statement that assigns a value to a variable must not be combined with data-retrieval operations.

So my question is, how can I assign the the AdminCost column to the @Amount variable?

I've also tried:

Declare @Amount numeric(6, 2)

Select @Amount = AdminCost From (Select AdminCost, max(ID)
    from tbl_pwe_tcr_DefaultAmounts
    where EffectiveDate < @EntryDate
    Group By ID, AdminCost)

but that doesn't work either.