Queries :: Add Comparatives To Grouped Totals Queries

I have a totals query of phone call charges by phone number and I want to show a "budget" amount for each number (same amount for all) and a variance against that budget.

How I can do this at the grouped (phone number) level rather than at the individual call level?

Please see current query below:

SELECT Call1CurrentTbl.電話番号（MSN）, Sum(Call1CurrentTbl.料金) AS 料金OfSum
FROM Call1CurrentTbl
GROUP BY Call1CurrentTbl.電話番号（MSN）, Call1CurrentTbl.[レコード区分], Call1CurrentTbl.表示区分
HAVING (((Call1CurrentTbl.[レコード区分])=2) AND ((Call1CurrentTbl.表示区分)=10));