Analytical Theory of Monotone Commodity State Development with Inflexion

A method of modelling commodity depreciation, based on the methodology of theoretical physics, is used to derive a deterministic linear motion equation of the second order to describe the degressive and progressive development of the instantaneous relative depreciation and price of a commodity over time in a model of market structure with perfect competition. The same approach is used to derive a non-linear motion equation of the second order for instantaneous relative depreciation with degressive/progressive development over time.