Year-Over-Year(redirected from YOY)
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The measure of performance in one year compared to the previous year. This is done so that growth or decline might be measured. For example, one might compare sales in 2009 to those in 2008. If a company sold 1,000,000 widgets in 2008 and 1,250,000 in 2009, this indicates 25% growth in sales, and is a positive sign for investors. See also: Quarter.