Negative in Red for Text&image charts

[Ivan_Yan]

Hi, I am using Text&image charts to show the KPIs as following(this graph is just a excel draft):

I want the  yty ratio to be green in positive and red in negative. However, I cannot find a place to do the formula for Colour in Qlik. I can only find the place to set the static colour.

Anyone knows how to deal with it? Or if there is other chart that can do the simliar result, which also works for me.