A bullwhip measure for a two-stage supply chain with an order-up-to inventory policy is derived for a general, stationary SARMA(p, q) × (P, Q) s demand process. Explicit expressions for several SARMA models are obtained to illustrate the key relationship between lead-time and seasonal lag. It is found that the bullwhip effect can be reduced considerably by shortening the lead-time in relation to the seasonal lag value. 
Measuring the bullwhip effect for supply chains with seasonal demand components