For doing calculations, as I have to ascertain whether all the effort was worth it or not.
So, I have this curve fitting against which I can compare my gas consumption based on the average outside temperature for the month. But his is done for a month, and I wanted to see if I could go to a lower level, so I found in the KNMI website a service from which you can download all kinds of meteo data for a time period.
I downloaded the average month temperatures for "De Bilt" as that is where I have been basing my calculations all these years, although not the closest station, and plotted it against the daily gas consumption. I couldn't go away without putting it here, so here goes, for the month of November:
LEGO Traffic Light
4 weeks ago