Gridchart Axis Headings

[#1]

I have a gridchart with the Y Axis headings populated by 0 through to 13 as per the result of a calculation.

However, I would like to show 13+ rather than 13.

Am I able to do this?

[#2]

i guess you can do this.

in dimension you can try writing below expression

if(fieldname<=13,fieldname,'13+')