How do I total expenses per month

Question

I am using the check register template in numbers.  I added a table to calculate a running total of expenses per category per month.  I can get the table to keep a running total of expenses per category, but have not been able to add the per month value.  How do I add that part into my formula. Specifically, my formula so far is =SUMIF(Transactions :: $Category,A2,Transactions :: Amount).  Now all I need is to add the month value so I can see how much I am spending per month per category.

Answer 1

Transactions
Beginning Balance
$126.37
Type
Date
Description
Category
Amount
Balance
Debit
3/19/12
Gas at Shell
Bills
$          (50.54)
$          75.83
Debit Card
3/20/12
Starbucks
Starbucks
$          (1.79)
$          74.04
Debit Card
3/21/12
Freebirds Austin
Food
$          (9.72)
$          64.32
Debit Card
3/23/12
Smokey Mo’s
Food
$          (7.00)
$          57.32
Deposit
3/26/12
Deposit
Deposit
$          100.00
$          1,444.57
Debit Card
Bills
$          1,444.57
DEP
Bills
$          1,444.57
DEP
Bills
$          1,444.57
Debit Card
Bills
$          1,444.57
105
Bills
$          1,444.57
DEP
Bills
$          1,444.57
Debit Card
Bills
$          1,444.57
Bills
$          1,444.57
Here is an example of the checking register table I am building
Category
Amount
Home
$          0.00
Food
$          (16.72)
Bills
$          (50.54)
Credit Card
$          0.00
Entertainment
$          0.00
Starbucks
$          (1.79)
Total
$          (69.05)
And here is an example of the table for "March" that I am building. But, I only want March expenses to add in this table.  Once April comes around, I want a new table to show expenses per category for that month. 
I am new to this community, to have patience please.