welcome to the forum hockeytemper.
how many miles do you have on your spark so far?
you might have to keep on driving your chevy spark a good 500-1000 miles before you get to see the real MPG's it's rated for. usually this is the case with new cars.
might be best if you keep us posted on your MPG's as you add more miles to the vehicle.
btw who's your favorite hockey team?