[USMA:11907] gasoline use

[RobertHB]

While my electric car is out of service, I drive a Chevy (Geo) 
Metro which goes 17 km/L.
The Insight is reported here to use 4.2 L/100 km.
I make this out to be 23.8 km/L.
So, the Insight is 40% better than my Metro.
Is that enough to junk the Metro?
                    Robert Bushnell