When the price of fuel is going through one of its mad fluctuation phases, it's impossible to tell if your fuel savings efforts are having any meaningful impact. If I just replaced a lot of planes with a more efficient model but the price of fuel also dropped by $12 there's no way to tell if my fuel cost savings were mostly just due to the drop in price or if the plane swap helped much. And when fuel is constantly climbing for weeks at a time while I'm replacing my fleet, watching my weekly fuel costs rise despite my efforts is demoralizing. It would help to know if my fuel savings efforts are at least blunting the impact of a fuel spike or if it's all pointless.
Seeing a graph that shows weekly fuel consumption on the Office page alongside the passenger and cargo graphs will help determine if swapping routes to planes that burn 150kg/hour less is really a good use of my time. It could go to the right of the Fuel Prices graph to give a complete picture of whether or not that new Fokker was worth it.
(And before anyone brings up the statistics page, that only ranks you against other airlines over the last quarter, it doesn't show you actual fuel burned per week over time.)