Learn how GROUPBY passes both subset and full arrays into LAMBDA in Excel, letting you compute percent shares fast and explain results clearly.

Carol M. Kopp edits features on a wide range of subjects for Investopedia, including investing, personal finance, retirement planning, taxes, business management, and career development. Monte Carlo ...

Microsoft Excel has been the premier spreadsheet software for decades, since outdoing the once venerable Lotus 1-2-3, the first killer app for PCs in the 1980s. And Excel's dominance has yet to be ...