Prints Taxes single time at Line Level against Items in RTF Report

HI,

i have 10 Items at line level, Item1, Item3, Item4 has same tax name and same tax Value, Item2, Item5,item8 has same and Item6, Item7, Item9, Item10 has same tax name and tax value.

in my report displays each tax in single line repeating but i want to display one tax name at one time at line level.

for example:

Tax Name and Value                              Total Tax

-------------------------------------------------------------------------------

VAT@5.5(Item1, item3, item4)                1000

VAT@7.5(Item2, Item5, Item8)                1475