You would need, for reporting, a formula - Rich Text field which you could then have the logic based on the date and what color the back ground should be. We have used similar.
var number totalDays = [Impact (0-5)]+[Likelihood (1-5)];
var text red = "<a style=\" text-decoration: none; background: #ea4335; border-radius: 5px; color: #fff; display: inline-block; width: 160px; text-align: center; padding: 8px 20px; font: normal 700 14px/1 \"Calibri\", sans-serif; text-shadow: none; \">"&$totalDays&"</a>";
var text green = "<a style=\" text-decoration: none; background: #34a853; border-radius: 5px; color: #fff; display: inline-block; width: 160px; text-align: center; padding: 8px 20px; font: normal 700 14px/1 \"Calibri\", sans-serif; text-shadow: none; \">"&$totalDays&"</a>";
var text yellow = "<a style=\" text-decoration: none; background: #fbbc05; border-radius: 5px; color: #fff; display: inline-block; width: 160px; text-align: center; padding: 8px 20px; font: normal 700 14px/1 \"Calibri\", sans-serif; text-shadow: none; \">"&$totalDays&"</a>";
var text gray = "<a style=\" text-decoration: none; background: #c2c2c2; border-radius: 5px; color: #fff; display: inline-block; width: 160px; text-align: center; padding: 8px 20px; font: normal 700 14px/1 \"Calibri\", sans-serif; text-shadow: none; \">Missing Rating</a>";
(If([Likelihood (1-5)]=0,$gray,
(If(IsNull([Impact (0-5)]),$gray,
(If([Impact (0-5)]+[Likelihood (1-5)]<=5,$green,
(If([Impact (0-5)]+[Likelihood (1-5)]=6,$yellow,
(If([Impact (0-5)]+[Likelihood (1-5)]=7,$yellow,
(If([Impact (0-5)]+[Likelihood (1-5)]>=8,$red))))))))))))
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Ryan Stanford
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