Quick, clean, and to the point

Apply number format

Windows shortcut 
Mac shortcut 

Apply the Number format with two decimal places, thousands separator, and minus sign (-) for negative values.

I also wanted to tell you in researching this formula problem, I combed through about 50 videos and websites. Yours was the most professional, easy to understand, and welcoming to a student who wishes to become more knowledgeable with Excel. -Devorah
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