# Forums

## Conflicting Data

My mind doesn’t rest well if simple logical issues can’t be reconciled. Here is my question:
After driving exactly 30 miles, the energy graph showed that my average Wh/mi was 272 (over the last 30 miles), but at the exact same time the trip display (again, at exactly 30 miles) showed that the average Wh/mi was 282. I just can’t reconcile the two. Can you help?

SCCRENDO | January 28, 2020

Slight differences in driving conditions and speed

T35LAX | January 28, 2020

@SCCRENDO

"... the energy graph ... at the exact same time the trip display ..." -> exact same driving condition and speed IMO

SCCRENDO | January 28, 2020

The energy graph does not show the speed. The elevation is a rough estimate on the graph. There could have been more losses due to air conditioner/heating with different temps. There is a coefficient of variation in the wh?m car calculation. I doubt this is 0. There are lots of possible variables that may be difficult to document. The difference is 10/272 which is 3.7%.

alewis | January 30, 2020

I think that the trip meters truly average the Wh/mi by literally dividing Wh's used by the miles drven. The energy graph, I believe, is using a funny round-about calculation to come to a different way of "averaging" Wh/mi over the previous 30 miles. For example, The energy graph told me I averaged 280 Wh/mi over the last 30 miles. I then drove for 2 miles averaging 150 Wh/mi and the energy graph average went UP to 295! It just so happened that at this time, 30 miles ago, a significant energy surplus (green plot) from the energy graph dropped, and I feel that this impacted the "average" Wh/mi (though it's not a true calculation.) Any thoughts?