Alltime.ini
Cumulus maintains a number of 'all time records' for the station -- highs and lows for many of the readings. These were stored in a database file (alltime.rec) however starting with Build 924 (version 1.8.9) of Cumulus this data is now stored in a text file which can be easily edited if needed.
The first time you run Build 924 or later of Cumulus it will convert your alltime.rec file into an alltime.ini file and use the ini file going forward. The alltime.ini file is located in the 'data' folder
Date, Time and Decimal formatting is as per your regional settings on the PC running Cumulus.
Example line of the file
[Temperature] hightempvalue=29.7999992370605 hightemptime=22/05/2010 16:13:00 lowtempvalue=-12.5 lowtemptime=20/12/2010 07:17:00 lowchillvalue=-12.5 lowchilltime=20/12/2010 07:17:00 highmintempvalue=17.2999992370605 highmintemptime=10/07/2010 lowmaxtempvalue=-4.30000019073486 lowmaxtemptime=20/12/2010 highapptempvalue=31.7999992370605 highapptemptime=22/05/2010 16:13:00 lowapptempvalue=-15.8000001907349 lowapptemptime=20/12/2010 07:17:00 highheatindexvalue=30.2000007629395 highheatindextime=22/05/2010 16:10:00 highdewpointvalue=19.8999996185303 highdewpointtime=20/07/2010 16:10:00 lowdewpointvalue=-13.5 lowdewpointtime=20/12/2010 07:20:00 [Wind] highwindvalue=18.1000003814697 highwindtime=07/02/2011 10:08:00 highgustvalue=38.4000015258789 highgusttime=07/02/2011 10:34:00 [Rain] highrainratevalue=114.300003051758 highrainratetime=23/09/2010 14:13:00 highdailyrainvalue=31.8999996185303 highdailyraintime=05/02/2011 23:44:00 highhourlyrainvalue=15.8000001907349 highhourlyraintime=23/09/2010 14:59:00 highmonthlyrainvalue=103.599998474121 highmonthlyraintime=01/02/2011 [Pressure] highpressurevalue=1043.30004882813 highpressuretime=26/01/2010 10:44:00 lowpressurevalue=965.700012207031 lowpressuretime=08/11/2010 15:42:00 [Humidity] highhumidityvalue=100 highhumiditytime=23/01/2010 01:10:00 lowhumidityvalue=21 lowhumiditytime=24/04/2010 12:10:00