ASOL shows the average age of outputs spent on a given day. It is a spent-side age metric, so it summarizes how old the coins were when they actually moved, not how old the held supply is.
A rising series means older outputs supplied the day’s spent set on average. A falling series means spending was dominated by younger coins. It is most useful with MSOL, Spent Volume Age Bands, and revived-supply thresholds, where the question is whether old-coin participation was broad or concentrated.
The main caveat is that ASOL is an average. A small number of very old outputs can pull it sharply higher even when most spent outputs were still young. That is why it should not be read alone.
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