Excel and 'Percent' Formats for Calculated Measures

Today I was with a customer and created a calculated measure that was formatted as a percentage. The formatting showed up fine in the cube browser but did not in Excel, which was a bit strange given that other percentage calculated measures on the cube seemed to be working fine. Now I knew that Excel doesn’t pick up the formatted_value of a cell in a cellset, but instead takes the format_string associated with each cell and interprets this as an Excel format inside a pivot table, and this explains why sometimes SSAS formats don’t work in Excel. So clearly something was going wrong with Excel interpreting the format string I’d defined.

Finally the guy I was working with, Andrew Baker, worked it out. Look at the two following calculated measures:

CREATE MEMBER CURRENTCUBE.MEASURES.C1 AS 0.99, FORMAT_STRING=’PERCENT’;
CREATE MEMBER CURRENTCUBE.MEASURES.C2 AS 0.99, FORMAT_STRING=’Percent’;

When you add them to a cube and browse the cube in the cube browser, you see this:

In Excel you see this:

What’s the difference? Yes, you guessed it, when it comes to the built-in SSAS format string types like ‘Percent’, Excel is case-sensitive. So a format string like ‘PERCENT’, while it’s valid from an MDX point of view, gets ignored by Excel whereas ‘Percent’ is correctly interpreted as a percentage format.