tl;dr - Winter makes a big difference. As do short trips.
Non heat pump Model 3 LR. Heating/AC on at 20C. No preheating.
This morning we got 72% (324Wh/mile) and 77% (304Wh/mile) - mostly A roads ~ 14 miles each way. I do have M option but didn't take it this morning.
This is our average efficiency (ie mileage vs rated miles - typically 290-300) since December. Trips over 5 miles, which rules out the short trips that disproportionally affect efficiency in early stages of a trip.
View attachment 766817
Now compare the same with April - September last year. Much better.
View attachment 766818
This is the same but averaged over 2+ years (3 winters, 2 summers - one mostly lockdown).
View attachment 766816
And this is lifetime average again, but filters out the regular early morning 'taxi run' which are often mixed A and M roads.
View attachment 766815