This comes from a feature request made for the Pirate Commodity Trader with Bleach. Here are the details:
"I want to be able to review an island's trade market. I want to be able to see all the commodities (or a given section) for trade at a market. I'd like to be able to limit this to "Best buy/Best sell, and total quantity at that price". And, if the data supports it, see what the prices used to be in the past."
One of the things this person asks for from PCTB is the ability to view historical information. This will be extremely problematic for this tool. It is not impossible, nor is it difficult to implement. The issue, however, is the data storage requirements. It's at least worth an experiment.
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