Changing Variables in Timeline

So to keep this as simple as possible, how would one change a variable, say a simple int or float, via the timeline?

I first thought of emitters but it seems I would need a whole new receiver for each unique change of the variable. Fine if I only changed one variable a small number of times, but likely overly cumbersome if I was changing multiple variables hundreds of times.

I would love to have a way a way I could just take a single receiver and add a way to assign said int to a value of 1 at second 3, then change it to 5 at second 4, then 2 at second 6, so on and so on. This would also not be random, but assigned directly by me on the marker(correct term?) in the timeline.

Any simple way of doing this?