That is a pretty open qst, work rates and engine load varies widely. I can't help you much with gph rates cos while I can can convert most metric to imperial pretty well, fluid is not one of them. Our 9600's held around 530 litres and in our conditions (medium load) would run about 10 harvest hours to a tank. I think 530 litres is around 140 US gallons, hence 14 gallons/hr but take that conversion at face value.
GM We checked our 9600 a couple times last fall in corn and it was consistantly in the 7.5 to 8 gal an hour range. This was running at 4 - 4.5 mph 8 row 36 cornhead and unloading on the go in irrigated corn.
I look more at gallons/acre. My average last year was .82 gpa in wheat, .97 in corn and .88 in beans. The highest was 1.2 gpa in 220-230 corn and lowest was .64 in good cutting beans (40-45) where you could really haul azz.