all stats are pretty much out of range IME. especially when up against those oven stats they put in their oven.
IF it has 2 slots in the collar around the knob shaft then it can be adjusted with long nose pliers by turning the collar. Very hit and mis though. Need to plot the temperature every 2 minutes with a digital thermometer over, say, 30 minutes after pre heating and average it out. will probably come to within 20-30 degrees which is about as good as it gets.