Average excluding selection

[canmarroig]

Hi, this is my data set

A     B         $

20    black    200

20    red       1000

30    white    10

70    blue      200

80    blue      300

90    blue      100

93    black     50

95    red        100

..........

i've a bar chart with my $ and i need to calculate avg of $ using A and B as dimension. No problem

Sales department (who hates me) asks to add a futher field with an avg for all A field with the same B field and if i select A=70 my average must be calculate without selected (80 blue + 90 blue).

Help me pls, tks

[sunny_talwar]

Well we def. are doing something similar, but I wanted to know what is another way of doing it. Thanks for sharing