Augmenting kW/h per 100km

Hey guys,

I have this second hand zoe from 2014 since september/october 2024.

That time it showed average 13.something kW/h per 100km.

Now it seems to be augmenting and is currently 16.1.
I have to say that it's winter and there are nights with -7 degrees C (19,4 Farenheit) in case it has something to do with the cold.

I don't know if it's a problem or if it's normal.

P.S. Battery SoH is 98%