If spreadsheets are your thing, but Microsoft Office isn't, you might want to give the open-source clone, GridCraft, a try.
Someone built a 14-tab spreadsheet, named it FINAL_v7_REAL.xlsx and left the company without explaining a single formula.
The Excel net present value formula: NPV = -$232,000 + $38,800 (1+0,10) -1 + $38,800 (1+0,10) -2 + $38,800 (1+0,10) -3 + … + ...
In addition to being free and open-source, LibreOffice offers other benefits, such as greater document privacy than Microsoft ...