We just descibed that we made 57 - 63 mpg from our 2006 Prius. However, we got a question about "resetting by itself -- energy/consumption screen.

What we wonder is that ..
We drove on 1-75 slow speed (because we can't go anywhere... all cars stuck because of the traffic....) that built up to over 60 mpg for a period of time. However, the next morning we continued driving back to Florida. It showed on the screen -consumption/energy dropped to nearly 0 (zero) and started bringing up to normal stage above 52 mpg again within 1 hour.

Why this happened ? We need to more about this.. Is this good or bad ? What need to be done about it ? Please explain and give us advice.. However, the car is normal and there is no indication of anything ??? at all.