Hi: I got my Prius Feb 2006, Now is 177,000 Miles (Yes, 283,200 kilo-miles). Because of 90% Freeway everyday, I got only 40 mile/ga (20 kilo/liter), If you have more local street driving, you could get 25% more mileage.
US Federal goverment require Prius with 100,000 miles warranty on the 500V (not the regular 12V one), California State goverment erquire Prius with 150,000 miles warranty. That's why US model Prius has no "EV switch" (which EU and Japan model has EV switch, so you can recharge your Prius at home).
Without EV switch, you only use top 40% of the 500V battery, then it will recharge from gas engin, so the 500V battery can last much longer to meet goverment required 100,000 or 150,000 miles warranty.