In addition to providing standard calculating formulas and functions, electronic spreadsheets provide modeling capabilities that allow users to describe real-world situations and then test a variety of possible outcomes using different numbers. This ability to perform a what-if analysis is a useful tool. Users can investigate what would happen if sales increase by 10 percent or decrease by 5 percent, or students can determine the semester grade implications of earning an "A" grade on the next examination—or a "B" or "C."