Description of problem:
I would like to create dashbord chart from custom report based on custom evm service attributes. I have attached to my all services custom attribute in format "key" -> "value". Value is the decimal number. I am able to create report from those custom attributes (EVM custom attribute: {Name,Value}), but I am not able to create chart because the attribute (EVM custom attribute: value) is not in the numeric format and there is no possibility to change to formatting.

Version-Release number of selected component (if applicable):
cfme-5.5.2.4-1.el7cf.x86_64

How reproducible:
requires custom attributes in vmdb

Steps to Reproduce:
0. have custom attributes in vmdb
1. create a report that uses custom attributes
2. create a chart widget based on this report
3. add to the dashboard

Actual results:
blank chart widget

Expected results:
chart widget with fully populated custom attribute data