Apologies Tom,
So I'm using the standard example xstats extension which has the following code:
# Now use a similar process to get statistics for the last 30 days.
days_dt = datetime.date.fromtimestamp(timespan.stop) - datetime.timedelta(days=30)
days_ts = time.mktime(days_dt.timetuple())
thirty_day_stats = TimespanBinder(TimeSpan(days_ts, timespan.stop),
db_lookup,
context='thirty_day',
formatter=self.generator.formatter,
converter=self.generator.converter)
which I assumed (probably wrongly) had all the same aggregation types as everything else as there wasn't any detail in the file.
Thanks as always. Think I have now been using Weewx on and off since version 2 and its always so impressive in its flexibility and stability.
Chris.