What type of mpg should I expect from my gen 2?

12 year old 2008 Prius Tspirit (UK) top spec.
Right now as I speak, I have 65.4mpg (UK) on the MFD, and I’ve done about 500 miles out of a full tank so far - might be able to stretch it to the magic 600+ miles out of a 45 litre fuel tank.

During the UK lockdown, I was able to achieve the figures below, driving to work (I’m a designated key worker) and back on virtually deserted roads and keeping to the speed limits.

Those readings are from the same tank of fuel I’m still using.
It dropped drastically when my normally 35 minute commute home turned into a nightmare - due to an accident on the highway which meant spending 3 hours travelling only 4 miles (out of the total 17 miles trip home) in the worst traffic congestion ever.

It took me 3.5 hours to get home.........hence the drop from 67.1 mpg - I was otherwise, on course to break my personal record of 66.0 mpg (UK) 634 miles, out of a full tank

Not bad for a 12 year old 2nd Generation Prius Hybrid


iPad ? Pro