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Table 4. Comparison of Shortage Cost between Proposed and Existing Condition
In the proposed condition and existing condition PT XYZ regional Jabotabek, did not experience a shortages inventory. So there is no cost to be incurred as a result of these shortage.
In the existing condition PT XYZ regional Jabotabek did not experience a shortages in the inventory starter pack but too much inventory should be stored in the warehouse. While on the proposed
condition, PT XYZ, not deficient, but also did not experience the shortage of inventory.
8. CONCLUSION
Based on the research objectives that have been set and the result from the data processing, the conclusions of this study are:
1. On October 2014, stater pack A207 have safety stock as 44.293. Stater pack A207 will be order if amount of inventory approaching the safety stock. The order will be do twice in October 2014, on
20 October 2014 with 15,463 as optimum order quantity and on 27 October 2014 with 92,667 with as optimum order quantity. The maximum inventory on first week is 412.738, second week is
320.071, third week is 227.403, and fourth and fifth week is 150.199. During October 2014 until September 2015, there are 49 times orders.
On October 2014, starter pack H008 have safety stock as 14.048. The reorder point will be happen if amount of inventory approaching the safety stock. There is no order for stater pack H008 on October
2014. The maximum inventory on first week is 123.054, second week is 104.199, third week is 85.344, fourth week is 66.489 and fifth week is 47.634. During October 2014 until September 2015,
there are 47 times orders. On October 2014, starter pack K103 have safety stock as 58. The reorder point will be happen if
amount of inventory approaching the safety stock. There is no order for stater pack K103 on October 2014. The maximum inventory on first week is 2.114, second week is 2.035, third week is 1,956
fourth week 1.877, fifth week is 1.798. During October 2014 until September 2015, there are 26 times orders.
On October 2014, stater pack L001 have safety stock as 120.449. Stater pack L001 will be order if amount of inventory approaching the safety stock. The order will be do five times in October 2014,
on 29 September 2014 162.26320 as optimum order quantity, on 6 October 2014 73.551 as optimum quantity, on 13 October 2014 73.551 as optimum order quantity, on 20 October 2014 73.551 as
optimum order quantity and on 27 October 2014 73.551 as order quantity. The maximum inventory on the first week is 42.445 and from second week until fifth week is 204.508.
On October 2014, stater pack S054 have safety stock as 120.093. Stater pack S054 will be order if amount of inventory approaching the safety stock. The order will be do twice in October 2014, on
20 October 2014 with 46.621 as optimum order quantity and on 27 October 2014 with 168.133 with as optimum order quantity. The maximum inventory on first week is 770.022, second week is
601.889, third week is 433.757, and fourth and fifth week is 312.245. During October 2014 until September 2015, there are 49 times orders. Another inventory policy for other stater pack and month
can be find on the attachment sheet.
2. Safety stock, optimum order quantity, reorder point and maximum inventory make some cost such as carrying cost, order cost, shortage cost which variable from total inventory cost. Total carrying
cost in proposed condition with P model periodic review with variant demand method is Rp.488.721.544, while the carrying cost resulting from the existing condition in PT XYZ regional
Jabotabek regional is Rp. 647.219.313. In the propose condition with use P model method in PT XYZ regional Jabotabek occurs savings 24 when compared with the carrying cost on the existing
condition. In the proposed conditions by using a model of P periodic review did not occurred savings when
compared to the cost of the actual condition. Because of on the proposed conditions, ordered quantities only a few quantity causing the high cost of the orders. The order cost in existing
condition is Rp.204.189 while in proposed condition is Rp 326.705. In the proposed condition and existing condition PT XYZ regional Jabotabek, did not experience a
shortages inventory. So there is no cost to be incurred as a result of shortage. In the existing The comparison of shortage cost the proposed condition and existing existing
Condition Total Shortage Cost
The percentage of savings Retrenchment
Existing Rp -
Rp -
The proposed Rp -
Semarang, 7 Oktober 2015
14 condition PT XYZ regional Jabotabek did not experience a shortages in the inventory starter pack
but too much inventory should be stored in the warehouse. While on the proposed condition, PT XYZ, not deficient, but also did not experience the shortage of inventory.
The total cost of inventory on the actual condition of PT XYZ regional Jabotabek is Rp.647.423.502. While the total cost of inventory in proposed condition using the P model periodic
review with variant demand is Rp. 489.048.273. Comparison of the total inventory cost between the proposed conditions with the existing condition have savings of Rp. 158.375.229 or savings of 32
from the existing condition. Carrying cost, order cost, shortage cost and total inventory for each stater pack can be find in attachment sheet.
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