How is the % complete column populated?  Also, why can't I add another column?  Specifically, the status column that shows completion by red/yellow/green buttons?


Hello Dwanda! Child rows (and rows not associated with hierarchies) percent column is entered manually. If you have dependencies enabled in your sheet, parent rows will show a weighted averaged of its child rows based on duration and entered percent complete. 



As for adding columns - only paid Admins and the sheet owner can add columns. If you are a free Admin or an Editor on the sheet, you cannot make structural changes to the sheet, including adding/removing columns.