Keep in mind production management is linked to your short and long term strategic plans - especially your defensive perimeter plan.
Below is the historic perimeter plan. If you expand further into Darwin/Northern/Western Australia, south of the Solomons and/or into Ceylon, you will expend far more resources early than the average bear in an effort to slow down the pace of the inevitable allied wave.
In my current game (DaBabes Scen 2 PDU on) I am in Dec. 42. I scored early victories against Allied carriers so I expanded my perimeter and have build up a significant victory point lead. This comes, however, at a cost of stockpiling HI, oil, and fuel that can help assure you don't crash the economy in 44.
In sum, your strategic plan and how well you have done up to this point in executing your plan massively impacts your stockpiling, production, and loss stats. Be careful about comparing your numbers to someone who has a very different strategic plan. Even if different, however, comparisons can be very helpful and there are some great players who will take the time to give insights and share experiences.
The bottom line, however, is what do the victory points look like on the last day and did you do better job of fighting ww2 than Japan (your goal cannot be "defeating" the allies in terms of taking and holding a lot of territory - that is impossible).
Managing the Jap economy is one of several games within the game (another one is China) and it is a ton of fun!
