Mallbot is a program that prowls the mall once a day, recording prices for items found. This process begins by searching for item nubmer 1 10 hours after nominal rollover hour, and searching for another item every 15 seconds until it is finished.
Everyone who wishes to make make use of this data.
Policies on how quickly after collection the data is available and duration it will remain up are still evolving. The code uses the freely available KoLBot.pm.
Caveats:
Data files are usually about 1.1meg, compressed.
Any line that begins with a # is a comment, for humans, and is usually the item name for the next section.
Lines are space-separated fields in this order:
The data tends to be sorted by item, then in increasing order of price, just as KoL returns them. This is not guaranteed not to change in the future.
For those interested for economics research projects, or the like, I have historical data beginning 18 September, 2004.