Rich text duration field

Hello,

I am attempting to create a rich text field that will change the color of the field if the field is a negative or positive number.  The field I am attempting to do this on is called [YTD Change-Incoming to Answer].  That field is a duration field that displays the number of seconds between last years incoming to answer and this years incoming to answer.  If the number is a positive number, I want the field background to be red, as it is a negative change.  This is the formula I have but it won't let me use < or > since the field is a duration field.  Any ideas?

If([YTD Change-Incoming to Answer] > "0" , "<div style=\"background-color:red;\"> Urgent</div>", [YTD Change-Incoming to Answer] )

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Courtneah Thomas
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