The column Grand Totals are not appearing because of trying to add Measure Values together. Tableau calculates Grand Totals only for multiple items within a measure, not across different measure values. There are two ways in which to display Grand Totals for Measure Values:
1. Instructions at the following Knowledge Base Article link: Grand Totals Do Not Show for Measure Values | Tableau Software
2. Pivot the data. This will most likely be the best option if you are looking to create a pie chart and/or display the percent of totals. Attached is a simplified workbook example of how the pivoted data would look like. Additional information about pivoting can be found here: http://onlinehelp.tableau.com/current/pro/desktop/en-us/help.htm#pivot.html
pivoted example.twbx 20.4 KB
Thank you Hanna,
Much appreciated. Very useful material to work on. Thanks!