Can do! Hmm, I don't think I've ever done a reading on something entirely in the past, so this should be interesting. I'd propose asking the Runes and using the spread "Wyrd, Werthende, Sculd," which is the Old English equivalent of the three Norns of Norse Lore, Urdh, Verdhandi, Skuld. Very roughly these are equivalent to "past, present, future," but with some nuance - Wyrd refers to what is "laid down" - already established and with force carrying forward (so, nothing inconsequential). Werthende means, roughly "becoming," and speaks to things unfolding, happening, growing from Wyrd. Sculd (pronounced "Shuhld" and etymologically linked with "should") is the most different from the rough approximation - it speaks not to what will definitely happen in the future, but rather, what "should" happen, with a meaning of debt, or obligation. In other words, from what has happened and is happening now, what is "owed" - the most likely outcomes as things stand.

Applying all of this to the past should yield something like this: what was the groundwork for the last decade from earlier parts of your life, what happened during that decade, and what kind of outcomes were/are most likely from all of that. This last ought to be especially interesting, to see if anything that seemed likely has already or might still be shifted.

Anyhow, if that works for you, I'll do the reading soon.

Cheers,
Jeff