My Leaf App

All, sorry if this should be posted elsewhere, but I can't find anything in my searches.
I keep a detailed account spreadsheet of my daily commute to determine optimal charging levels, etc. vs charging at work. In doing so and through use of details from My Leaf app I am running into a discerpancy I would like your feedback on:
2 days ago: 20 mile commute, Percentage charge used 15% (58 down to 43%), computer says 3.8mi/kwh and 5.33kWh total consumption
Today: 20 miles commute, Percentage charge used 18% (52 down to 34%), computer says 4.4mi/kWh and 4.67kWh total consumption

Both commutes under similar temperature and driving styles, no changes. So how can a more efficient drive (today) of 4.4 use more percentage charge than a less efficient (2 days ago) drive of 3.8?? Is this a computational problem somewhere in the app? All the other numbers besides percentage charge make sense to me. How can a more efficient drive today use more charge?

Any help?

Year and model Leaf? My guess is that the climate control use isn't being taken fully into account, and that the energy use estimate is based mainly on the traction motor power consumption. I could be mistaken. What was the weather like on those two trips?

I find the app efficiency readings to be pretty aligned to Leafspy and dash efficiency calca. % used on dash is less reliable as different parts of the 0-100% are not linear power usage. Between 80 and 25% the car is slowly building a buffer and hiding it to prevent you from getting stuck.