Experimental research has shown that human subjects do not have a good perception of the future consequences of their current actions. One can therefore expect that in situations involving dynamic externalities, the outcome of individual decisions will be very inefficient. Static externalities in this kind of dynamic environment may enhance the perception of common property of the resource, leading to a more efficient exploitation. In order to evaluate this hypothesis, we compare the efficiency of the CPRs exploitation by studying an N-person discrete-time deterministic dynamic game of T periods fixed duration. The objective function is stage-additive and depends on a state variable, whose dynamic evolution is linked to past decisions of all players. The players have to decide whether to use a private good or, by paying a lump-sum fee, to extract on one of two imperfectly substitute Common-Pool Resources. The observations are confronted to three benchmark outcomes corresponding to distinct behavioural assumptions: (a) sub-game perfection, (b) joint payoff maximization, and (c) myopic behaviour