Spreadsheets are active software based tables used to express numerical values. (The format and name are derived from an old manual system.) A spreadsheet is commonly used to tabulate data inputs. Spreadsheets use formulas to process data and perform integrated calculations. They're primarily used in business for financial statements, but are also commonly used for production of breakdown analyses and graphs. The best known spreadsheet formats are MS Excel and Lotus, developed in the 1980s and introduced worldwide by the 1990s. Spreadsheets have now standardized most of the old style accounting methodologies and are a primary source of raw data.