Structure Formula: Display the Variance Result in Color

[Keiko Kamiya]

Hello,

I am trying to show the variance between the sum of Original Estimates compared to the sum of Time Spent rolled up to the Epic. 

I'd like to color-code the result of the variance output, however I have a hard time making a variable for variance:

IF TYPE = "EPIC":

WITH variance = (sum#children{originalestimate}/3600000 - sum#children{timeSpent}/3600000)
/
(sum#children{originalestimate}/3600000):

IF (variance < 20):
":panel[variance]{color=green}"
ELSE if (variance > 20):
":panel[OVER 20%]{color=red}"
ELSE IF (variance <= 0):
":panel[UNDER 0%]{color=blue}"

It's set to format: Markdown. Can someone assist? Much appreciated!