Editing groups of events in micro edit

Can't find this in threads or the manual.
Apols if it's there and I've missed it...

Am wondering if it's possible to alter groups of data simultaneously in micro edit,

e.g. in a particular channel, if I want to change the velocity of all notes by the same amount, or to a particular value, is this possible or do they each have to be changed individually?

Have tried selecting groups of events but selecting the relevant column before or after doesn't seem to work.

Thanks.