Excel has a number of functions to help you round numbers, and each one does a slightly different job.
One of these, the INT function, will round data down while removing all decimal places leaving only the whole number or integer.
Unlike formatting options that allow you change the number of decimal places displayed, the INT function actual alters your data and can, therefore, affect calculations.
To find out all the details, read this short, but absorbing tutorial on Excel's INT Function.
More Rounding Number Functions
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