the ACT.F reading is set at 'per minute' and can't be changed. That's one of the things you don't get with the cheaper 0-series controls. On 15/16/18 there is another item that shows actual feed/rev when the feed rate override knob is changed plus or minus.
The cheaper controls show FEED/REV but it's only the programmed feed rate. If you override it the ACT.F changes (which of course is not helpful because it's feed/minute) but FEED/REV stays the same as per the programmed feed rate.
I believe this is the same for 21-series as well.
In any case, it's simple to work it out from your programmed feed rate. work out 10% of your programmed feed rate and multiply it by how many 10-percents you increased or decreased and add/subtract to your programmed feed rate.
example: programmed feed is 0.012 and over ride is + 20%
0.012 / 10 = 0.0012 (i.e. move decimal point one place to the left)
0.0012 * 2 = 0.0024
0.0024 + 0.012
Doing it this way these calcs can be done in your head, no calculator is required.
Then simply update your program with this feed rate