Repigmentation

Started tacrolimus and uvb light about 6 months ago. I have segmental vitiligo so I understand it will be harder. I only got a few spots which got color back and that was in the first three months. After that progress has been slow the spot has gotten smaller a little bit almost shrinking not to noticeable but there has been some slight progress. I wondering if this is good progress or is this to slow of a progression. Yes I’m using uvb three times a week.