I have a 2-yr old Honda Jazz petrol hybrid and just had a 2-yr service. I notice that the indicated mpg has gone down from 62 to 42 mpg. Can this be true, as it's a big decrease? What could be causing this? I am a cautious driver doing only about 2,500 miles per annum. And I always have the car in 'Economy' mode?

Same thing is happening to me with 18 month old Crosstar. Down from 63 to 53 in 10 months. AI tells me it’s winter driving. All systems on using battery. Hoping it gets better in summer!!