I have a column chart that records the amount of hours/minutes (y axis)
people have been late for each week (x axis). On the y axis I want to change
it so that the intervals are at 5 minutes intervals, e.g. 5 minutes late, 10
minutes late, 15 minutes late etc.

I've looked at the scale options that Excel has set and I can't work out how
or if I can change the scale to what I want.