Is the default frequency of generation of the longer-term images (week, month, and year) displayed by the report index page documented somewhere? I cleared out some junk (data from when the station was in a a previous location) from my weewx database, and was somewhat surprised, after leaving what seemed like a reasonable time for new reports to be generated, to see the deleted data still displayed on the 'year' reports. After a bit of spelunking and checking of file dates, it appears that the 'day' images are updated at each archive cycle (5 minutes, in my case), the 'week' and 'month' images are (probably) both updated 'every hour, on the hour', and the 'year' images are only updated every day at midnight. This makes perfect sense, in terms of avoiding pointless processing, but I can't find it documented anywhere - the implication I previously took from the documentation was that every image was updated every archive cycle. If this default isn't currently documented, it probably deserves a note somewhere.