To keep an area of a worksheet visible while you scroll to another area of the worksheet, you can lock specific columns in one area by freezing them.
In Windows Vista and Windows 7, features in the PowerPivot window are available on a ribbon, which is discussed in this topic. In Windows XP, features are available from a set of menus. If you are using Windows XP and want to see how the menu commands relate to the ribbon commands, see The PowerPivot UI in Windows XP.
To freeze columns
In the PowerPivot window, select the table that contains the columns that you want to freeze.
Select one or more columns to freeze.
On the Home tab, in the View group, click Freeze.
A frozen column moves to the front of the table. Additional columns that you freeze are positioned next to the first column that you froze. If you later unfreeze the column, it will not be moved back to its original location.