Creating a Measure that can calculate timeframe based on slicer filters?

I have some Sales data that is provided with dates, and I have presented that information on a page I made with Year/Month filters.

Someone asked me if I can create visuals that provides the Sales data in an Average Daily form. Is there a way that I can create a measure that can calculate this for me? It seems I need to find a way to divide Sum of Sales by the Difference in Days between the first and last dates of my filtered timeframe, but I have no idea if its even possible for a measure to obtain this date info from slicers.

If anyone has any suggestions on whether this is possible or if there is a better alternative that would be really appreciated.