simple formula

Hey All,

I've a formula Numeric Formula field that calculates Units Remaining. 

[Weekly Units]-[# Units Used]

This works. Now I'm trying to create a message if this field goes NEGATIVE. 

if (([Weekly Units]-[# Units Used])<0, ToText("TOO MANY UNITS USED, TRY AGAIN"),
if (([weekly units]=[# units used]),"zero",
([weekly units]-[# units used]))))

I'm receiving a Formula Syntax Error for the last line: "Expecting Text but found Number". If this is a formula NUMERIC field, why am I getting this message?

Here are other variations that I've tried for that last  line, but still get the same message:

(ToNumber([weekly units])-ToNumber([# units used]))))

(ToNumber([weekly units]-[# units used]))))

Thanks in advance! Mary


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Mary Perkins
M3TR1CS Business Solutions
mary.perkins@m3tr1cs.com
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