I have a 2007 grey metallic myvi 1.3 auto.

I recently serviced the car.

Auto oil, motor oil and balancing wheels.

But recently I realised that my mileage during 2007-2009ish was around 450km / full tank.

Now i barely get 350km / full tank.

Any suggestions?

Here are some additional info that may help:

I've yet to get my air-con serviced, I need some suggestions on reputable aircon service in JB.
I've always kept with my maintenance schedule on engine oil change etc.
Tyre pressure is approximately 210