Token prices move in steps: a vendor reprices a model and it stays there for months. This is every step of 50% or more, last 90 days, by the vendor that made it. Aggregators are excluded because their listed price is whichever routed endpoint is cheapest that day, and that churn is not a repricing.
Free accounts see the last 90 days. Basic extends the feed to 12 months, Premium to the full history with CSV export.