The second period carries first-period ending inventory forward.

highlighted = computed this step

Second Period Balance

The second period starts with first-period ending inventory.

second beginning=first ending\text{second beginning} = \text{first ending}
Inventory balance tableThe table recomputes each ending inventory.period inventory balancebeginproddemandendfirst period201009030second period3010011020

Second Period Ending Inventory

Second-period ending inventory is 20 units.

30+100110=2030 + 100 - 110 = 20
Inventory balanceThe chart follows inventory through two periods.aggregate inventory balancebegin inventory 20; base final 20casep1 prodp1 demandp1 endp2 prodp2 demandfinalgainbase100903010011020baselinewhat-if10590351051103010basebegininv 20period 1inv 30period 2inv 20prod 100demand 90prod 100demand 110what-ifbegininv 20period 1inv 35period 2inv 30prod 105demand 90prod 105demand 110what-if final 30; gain 10deterministic aggregate inventory arithmetic only