Auto Filter difference

[lgenerator]

I am using the data auto filte function to drill down to a single variable in a list of variables. When I use the filter to drill down I can get the individual total to change using the formula =SUBTOTAL(9,C2:C5), however I can not get the week over week change to update when using the filter. In the example below if I filtered by Sample B by A I would want that week over week number to be 29-12, and for B 22-11. The sample C would be a running total of week over week. The formula I am currently using is =ABS(C12-C8). Any thoughts, feel like this is easy but it's stumping me?
[TABLE="width: 220"]
<TBODY>[TR]
[TD]Sample A</SPAN>
[/TD]
[TD]Sample B</SPAN>
[/TD]
[TD]Sample C</SPAN>
[/TD]
[/TR]
[TR]
[TD]1</SPAN>
[/TD]
[TD]A</SPAN>
[/TD]
[TD="align: right"]3</SPAN>
[/TD]
[/TR]
[TR]
[TD]1</SPAN>
[/TD]
[TD]B</SPAN>
[/TD]
[TD="align: right"]5</SPAN>
[/TD]
[/TR]
[TR]
[TD]1</SPAN>
[/TD]
[TD]C</SPAN>
[/TD]
[TD="align: right"]7</SPAN>
[/TD]
[/TR]
[TR]
[TD]1</SPAN>
[/TD]
[TD]D</SPAN>
[/TD]
[TD="align: right"]12</SPAN>
[/TD]
[/TR]
[TR]
[TD]2</SPAN>
[/TD]
[TD]A</SPAN>
[/TD]
[TD="align: right"]12
[/TD]
[/TR]
[TR]
[TD]2</SPAN>
[/TD]
[TD]B</SPAN>
[/TD]
[TD="align: right"]11
[/TD]
[/TR]
[TR]
[TD]2</SPAN>
[/TD]
[TD]C</SPAN>
[/TD]
[TD="align: right"]18
[/TD]
[/TR]
[TR]
[TD]2</SPAN>
[/TD]
[TD]D</SPAN>
[/TD]
[TD="align: right"]20
[/TD]
[/TR]
[TR]
[TD]3</SPAN>
[/TD]
[TD]A</SPAN>
[/TD]
[TD="align: right"]29
[/TD]
[/TR]
[TR]
[TD]3</SPAN>
[/TD]
[TD]B</SPAN>
[/TD]
[TD="align: right"]22
[/TD]
[/TR]
[TR]
[TD]3</SPAN>
[/TD]
[TD]C</SPAN>
[/TD]
[TD="align: right"]24
[/TD]
[/TR]
[TR]
[TD]3</SPAN>
[/TD]
[TD]D</SPAN>
[/TD]
[TD="align: right"]33
[/TD]
[/TR]
[TR]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD]Team Total</SPAN>
[/TD]
[TD][/TD]
[TD]108</SPAN>
[/TD]
[/TR]
[TR]
[TD]Individual Total</SPAN>
[/TD]
[TD][/TD]
[TD]27</SPAN>
[/TD]
[/TR]
[TR]
[TD="colspan: 2"]Weekly Change</SPAN>
[/TD]
[TD]?</SPAN>
[/TD]
[/TR]
</TBODY>[/TABLE]