Assessment of the Impact of Changing Activities’ Start Times on Cash-Flow Parameters

Contractors usually manage multiple activities within a single project in which activities’ start times are controlling the values of cash-flow parameters. Since, in any given schedule, the start time of activities vary while their dependencies are maintained, the other cash-flow parameters vary. Therefore, Simulation technique has been employed to generate schedules and their associated cash flow parameters by randomly specifying the activities’ start times between their respective early and late start times. Uniform discrete probability distributions are assumed for the activities’ start times. In addition, the simulation model considered the stochastic nature of cash in and cash out transactions in the cash flow model considering the impact of 43 qualitative factors. Three scenarios are defined; each incorporating a different number of qualitative factors which impact the project cash inflow and cash outflow transactions. Advanced sensitivity analysis is performed to measure the impact of changing the start times on cash flow. The activities’ criticality to cash-flow parameters is assessed by evaluating the number of times a given activity determined a particular cash-flow parameter over the number of runs. This criticality measurement offers project managers useful criteria with which to identify the activities that are most urgent to be completed on time. Keywords: Cash flow forecasting mode; Activities’ criticality; CPM; Simulation