Supply chain management in military logistics often deals with a number of variables in predicting cost, deterioration, consumption, and future demand. The US Military's categorical supply classification was developed in such a way that categories of supply with similar consumption variables are grouped together for planning purposes. For instance peacetime consumption of ammunition and fuel will be considerably less than wartime consumption of these items, whereas other classes of supply such as subsistence and clothing have a relatively consistent consumption rate regardless of war or peace. Troops will always require uniform and food. More troops will require equally more uniforms and food.
In the table above, each class of supply has a consumer. Some classes of supply have a linear demand relationship - as more troops are added more supply items are needed - as more equipment is used more fuel and ammo is consumed. Other classes of supply must consider a third variable besides usage and quantity: time. As equipment ages more and more repair parts are needed over time, even when usage and quantity stays consistent. By recording and analyzing these trends over time and applying to future scenarios, the US Military can accurately supply troops with the items necessary at the precise moment they are needed.[18] History has shown that good logistical planning creates a lean and efficient fighting force. Lack thereof can lead to a clunky, slow, and ill-equipped force with too much or too little supply.