How to create (and prepare the data for) a Sankey diagram

I deal in the basics of an ERP system, we take in data, and produce reports, lists, lists, lists. Mostly operational type reports. Every now and again we will throw up a pie chart or bar chart and everyone is like blown away because it’s colorful …

The Dean now wants a Sankey diagram for changes to Academic Majors – so this is a flow of initial selection of major to final graduation major. Most will stick with their original choice.

I see on Google it’s a flow style chart (https://developers.google.com/chart/interactive/docs/gallery/sankey), like the classic steam engine measurement, and even Napoleon’s invasion of Russia (https://en.wikipedia.org/wiki/Sankey_diagram).

I’m looking for tips on how to produce this. Excel looks like it’s up to the task (https://mychartguide.com/how-to-draw-sankey-diagram-in-excel/?unapproved=1719&moderation-hash=f3ea3edb766fc2dd17971a864b195541#comment-1719).

If Excel is up to the task, then my challenge is preparing the data. Right now I have an audit trail of prior major, newly selected major, and Student Id. So at the core it’s three fields: Student Id, Old Major, newly selected major, plus of course Race-Ethn and gender.

I have no idea if this data structure will work, but I’m thinking the software could wind it’s way through Student Ids and Majors for a flow line, showing original majors on the left and final majors on the right.

Most people actually stick with their original major. Some however, change 2-4 times.

So just looking for some tips on software and data prep