Charting Bug - Pie Charts do not recognize numbers as a category

Hi,

 

I was trying to create pie charts on a single feature using a field which has numbers and text as categories (100, 200, 300, N/A, L/R, etc) and the field is string type. But the numbers are not recognized as categories, only text values such as N/a & L/R are recognized as categories for the pie chart. This seems like a bug to me in the latest HTML5 viewer - 2.5.2

 

Thanks.