Drill hole size minimizing in NCdrill Parameter

For my board file, i had placed the NC drill legend below the board. After that in case i want to minimize or maximize the drill sizes in the drill parameter is not get edited.

In case of layout, the drill sizes can be directly edited in the table.But how it is possible in PCB editor.
 For Eg: 0.8, 0.864 drill sizes should be maximized to 1.0 means, how can i edit the drill sizes. any way to change the drill sizes in the parameter table.



Thanks & Regards
Dhamodharan