For the benchmark case, for all x> 0.1 % we have W|P=PSS(0)> 0. A marginal decrease in emissionsper output ratio reduces welfare. The relationship of W|P=PSS(0)with respect to x (which is a proxyfor s) mirrors the result obtained analytically for the behavior of W|P=PSS()in the limit case wheres→ ∞. The larger the damage parameter, the more likely a decrease of the emissions per output ratiowill be welfare reducing.Let Z ≡ P0/PSS(0). That is, Z is a parameter that sets the initial level of the stock of pollution relativeto the steady state stock of pollution. Fig. 4 shows that the graph of W|P=Z∗PSS(0)is a strictly increasingfunction