The Custom Column Management page allows you to choose the order columns (including custom columns) are shown on the timesheet, and how the weekly information from the is transformed into monthly information for the Analysis By Month pages:
Column: The name of the column
Type: The type of the column. If the type is incompatible with TeamTime (e.g. User, Lookup), you will be warned here
Order: The order in which to display the columns (only available to site administrators)
Transform: There are three options for each column transform:
Setting the Transform to Group will also stop the timesheet from warning you about duplicate entries when this column contains unique values.
To add, edit, or remove columns from the timesheet, follow the link at the top to directly access the TeamTime Content Type.