Index 100

Good afternoon, I am wondering if INDEX100 is the correct way to go for what I want and then, if so, how to use it?

Basically I have two sets of dates. The first being the PICKUP date and the second being the DEPARTURE date. This is calculated at a shipment level so each shipment that is moved will have a Pickup to Departure lead time. As time goes on we generate many shipmemts over many months. I would like to be able to plot a graph using the median of 'departure - pickup' for a chosen date range ie say October 2019 as the base line. So if October 2019 ovall median was 22 then that would be the base line all other months are scored against. So if November's median was 26 days then that would be an 18.18% increase etc etc. Once I have the numbers I can use a scatter graph or something suitable to plot on.

If you have any good thoughts around this I would appreciate it.

thanks
Marc