Totals

I want to group and sub-total based on a SBU - Strategic Business Unit:
 
 <Customer>
  <  <CustomerNumber>12345</CustomerNumber> 
  <  <CustomerName> CORPORATION</CustomerName> 
  <  <SBU>F</SBU> 
  <  <OrderNumber>12345</OrderNumber> 
  <  <ItemNumber>12345</ItemNumber> 
  <  <ItemDesc>Test</ItemDesc> 
  <  <LOD>12/12/02</LOD> 
  <  <PreInc>35.17</PreInc> 
  <  <PostInc>37.37</PostInc> 
  <  <ChangeAmount>2.20</ChangeAmount> 
  <  <ChangePercentage>6.26%</ChangePercentage> 
 </Customer>
 
 
There are 4 different SBU's and I want to sub-total at the end of each SBU.
How can I do this?