Change color attribute on an entry in CONCAT

Hello,

I need to be able to change the color of a single entry in a concatenated string, not the entire string I'm concatenating several text fields and a summed entry to create a message. If the summed entry is positive it will default to black but if it is negative it needs to be red and in parentheses.

example:

=CONCAT("This ","is a positive field - ",TEXT(SUM(1.50+2.00),"$##.00")) should be:

This is a positive field $3.50

While:

=CONCAT("This ","is a negative field - ",TEXT(SUM(1.50-2.00),"$##.00")) should be:

This is a negative field ($3.50)

Help, please. I've tried all I can come up with and all suggestions revolve around changing the color of the entire cell, not just one entry in a formula.

TheOldPuterMan (AKA John)