if you don't read SQL, let me know and I can elaborate, but here's the query that runs to update that graph:
Other graphs are powered by the queries from that folder, they correspond by name. To answer your question more directly,
the editing team, in the example you asked about, is computing "attempted saves" / "loads" and doing that computation for every 24 hr. period. Here "loads" is when they see a "ready" event, I think basically when the editor is ready to start editing but I'd have to check their instrumentation code to be more exact.