Cumulus Support

I've noticed that any month or day that has no recorded values in it yet, seems to have been set to either 999c, -999c, 9999.00 hPa etc. should the values not even show a value or be zero?

Temperature and Humidity
Highest Temperature -999.0 °C at 22:24 on 04 April 2016
Lowest Temperature 999.0 °C at 22:24 on 04 April 2016
Highest Dew Point -999.0 °C at 22:24 on 04 April 2016
Lowest Dew Point 999.0 °C at 22:24 on 04 April 2016
Highest Apparent Temperature -999.0 °C at 22:24 on 04 April 2016
Lowest Apparent Temperature 999.0 °C at 22:24 on 04 April 2016
Lowest Wind Chill Temperature 999.0 °C at 22:24 on 04 April 2016
Highest Heat Index -999.0 °C at 22:24 on 04 April 2016
Highest Minimum -999.0 °C at 22:24 on 04 April 2016
Lowest Maximum 999.0 °C at 22:24 on 04 April 2016
Highest Humidity 0 % at 22:24 on 04 April 2016
Lowest Humidity 999 % at 22:24 on 04 April 2016
Highest Daily Range 0.0 °C on 04 April 2016
Lowest Daily Range 999.0 °C on 04 April 2016
Rainfall
Highest Rain Rate 0.0 mm/hr at 22:24 on 04 April 2016
Highest Hourly Rainfall 0.0 mm at 22:24 on 04 April 2016
Highest Daily Rainfall 0.0 mm on 04 April 2016
Highest Monthly Rainfall 0.0 mm April 2016
Longest Dry Period 0 days to 04 April 2016
Longest Wet Period 0 days to 04 April 2016
Wind
Highest Wind Gust 0.0 mph at 22:24 on 04 April 2016
Highest Wind Speed Average 0.0 mph at 22:24 on 04 April 2016
Highest Daily Wind Run 0.0 miles on 04 April 2016
Pressure
Lowest Pressure (sl) 9999.00 hPa at 22:24 on 04 April 2016
Highest Pressure (sl) 0.00 hPa at 22:24 on 04 April 2016

Cumulus doesn't have a concept of 'no value'. The starting values are in general chosen to be obviously uninitialised. They would normally be set to correct values on the first reading, or at least at the end of the first day.