I want to diplay the cumulative total on the XSLT List View webpart in SharePoint 2010 as below, is that possible?
Default view:
Expected View:
In order to achieve this I would try focusing from the Client Side directly, by using JavaScript or jQuery to find the group aggregations, evaluating them, and pasting the value in the location you need. jQuery would allow for selection of the rendered HTML tags that contain the values. Related links:
http://sharepointontop.blogspot.com.ar/2012/05/get-value-of-selected-checkbox-in.html
Format part of the column value in a ListView Web Part
If you want this to be incorporated directly in your Web Part, the I suggest following an approach recommended in this other question.