This graphic comes from a dynamic asset allocation problem in railroads. The system, which is now in production at Norfolk Southern railroad, is the first production implementation of a stochastic, dynamic programming model in freight transportation. The model is based on the Ph.D. dissertation of Huseyin Topaloglu (now a professor at Cornell University) for stochastic, integer multicommodity flow problems. The original research was modified to handle multidimensional attribute problems, with millions of asset types.