Why is my 2005 Honda Accord Hybrid show low mpg?

Recently purchased the vehicle. I mainly drive it to the market and nearby places and I noticed that the MPG display on the dash reads anywhere 8-15 mpg. I'm really bummed if this is what I'm getting because I purchased this car to get good mileage. Please do help!

Is the dash display set for "Instant economy"? Ignore that. Set it for average or do like most folks and fill it, drive it, refill it and do the math.

I'm pretty sure the display is wrong, just do the mats, however check the air pressure and change the spark plugs, you can see noticeable gas economy and this mods are very cheap my advice get some NGK spark plugs