1. Demand Variability: The Bullwhip Effect Dr. Joe Hage
2008-2014. Copyright, Dr. Joe Hage. Proprietary Information. All
Rights Reserved. 1
2. Demand Variability 1/2 Increases as one moves up the supply
chain away from end customers Small changes in customer demand may
result in large variations in orders placed upstream Network can
oscillate in very large swings as each organization in the supply
chain seeks to solve the problem from its own narrow, often
self-serving, perspective 2008-2014. Copyright, Dr. Joe Hage.
Proprietary Information. All Rights Reserved. 2
3. Demand Variability 2/2 Sources of Variability Demand
Variability Quality Issues Strikes and Disruptions Plant Shutdown
Variability coupled with time delays in the transmission of
information up and down the supply chain and time delays in
manufacturing and shipping goods up and down the supply chain
create the Bullwhip Effect 2008-2014. Copyright, Dr. Joe Hage.
Proprietary Information. All Rights Reserved. 3
4. Bullwhip Effect 1/2 Distortion of orders along the supply
chain, where small fluctuations in end customer demand result in
amplification of demand upstream, aka Demand Amplification The term
bullwhip, where just a small flick of the wrist at the handle will
create a large crack of the whip at its tip 2008-2014. Copyright,
Dr. Joe Hage. Proprietary Information. All Rights Reserved. 4
5. Bullwhip Effect 2/2 Quantities Ordered by Distribution
Centers Quantities Ordered by Retailers time Manufacturers
Quantities Ordered by End Customers time time Distribution Centers
Fluctuation Increases 2008-2014. Copyright, Dr. Joe Hage.
Proprietary Information. All Rights Reserved. Retailers Fluctuation
Increases 5
6. Cracking the Whip 2008-2014. Copyright, Dr. Joe Hage.
Proprietary Information. All Rights Reserved. 6
7. The Bullwhip Effect Orders Bottled Water Corporation Orders
50 Orders (Thousand Cases) 45 40 35 30 25 20 15 10 5 0 1 2 3 4 5 6
7 8 9 10 11 12 13 14 15 16 17 Weeks Consumers Retailer 2008-2014.
Copyright, Dr. Joe Hage. Proprietary Information. All Rights
Reserved. Wholesaler Distributor Factory 7
8. The Bullwhip Effect Cost Bottled Water Corporation Inventory
Cost 160 140 Cost (Million $) 120 100 80 60 40 20 0 1 2 3 4 5
Retailer 2008-2014. Copyright, Dr. Joe Hage. Proprietary
Information. All Rights Reserved. 6 7 8 Wholesaler 9 Weeks 10
Distributor 11 12 13 14 15 16 17 Factory 8
9. The Bullwhip Effect Stockouts Bottled Water Corporation
Stockout 50 Quantity (Thousand Cases) 40 30 20 10 0 1 2 3 4 5 6 7 8
9 10 11 12 13 14 15 16 17 -10 -20 -30 Weeks Retailer 2008-2014.
Copyright, Dr. Joe Hage. Proprietary Information. All Rights
Reserved. Wholesaler Distributor Factory 9
10. Bullwhip Effect Creates Problems 1/2 High Inventory Levels
Inventory Cost Demand Fluctuation / Variability Low Service Level
(Backorders / Backlogs) Efficiency Customer Satisfaction Friction
among Supply Chain Partners 2008-2014. Copyright, Dr. Joe Hage.
Proprietary Information. All Rights Reserved. 10
11. Bullwhip Effect Creates Problems 2/2 To cope with peaks and
valleys, variation in demand along the supply chain requires:
Shipment Capacity Production Capacity Inventory Capacity Most of
the time capacity is idle Resulting in significant costs and
investments Conclusion High overall cost in the supply chain
Unhealthy competition between supply chains and networks, not just
between individual companies! 2008-2014. Copyright, Dr. Joe Hage.
Proprietary Information. All Rights Reserved. 11
12. Structure Creates Behavior Different people in the same
organizational structure produce the same (or at least similar)
results Losses Events (Backlogs/Surges/Friction) Behavior (Process
Oscillation/Demand Variation) Structure 2008-2014. Copyright, Dr.
Joe Hage. Proprietary Information. All Rights Reserved. 12
13. Reactions Typical organizational response is to find the
person responsible, i.e. the person placing the orders or the
inventory manager, and blame him or her However, such a response is
inappropriate because different people following different decision
rules for ordering have created similar variations and oscillations
The structural setup must be changed 2008-2014. Copyright, Dr. Joe
Hage. Proprietary Information. All Rights Reserved. 13
14. Factors Contributing to Bullwhip Effect 1/2 Demand
Forecasting Usage of aggregate and thus inaccurate data does not
allow for good predictions High variability leads to continuous
adaptations of order policies, thus increasing variability upstream
Lead Time Longer lead times create uncertainty Requires high safety
stock levels Reduces flexibility and adaptability to unforeseen
changes in demand Inflated Orders In time of shortages, suppliers
place big orders when the expectation is to be on proportional
allocation 2008-2014. Copyright, Dr. Joe Hage. Proprietary
Information. All Rights Reserved. 14
15. Factors Contributing to Bullwhip Effect 2/2 Batch Ordering
At one stage in supply chain leads to observing high variability at
next stage upstream One week large order followed by weeks with no
order Contributors: fixed ordering costs, transportation and price
discounts Price Fluctuation Stock up when prices are lower are
leading to large orders Promotions and discounts 2008-2014.
Copyright, Dr. Joe Hage. Proprietary Information. All Rights
Reserved. 15
16. Lessons In traditional supply chains, information about
consumer demand is only passed upstream through the orders placed
with aggregated figures Information is therefore lost resulting in
high buffer stocks Even if each partner acts optimally
individually, the result is less than optimal for the entire supply
chain Result is higher prices, lower sales, less margins However,
competition is now supply chain against supply chain and network
against network 2008-2014. Copyright, Dr. Joe Hage. Proprietary
Information. All Rights Reserved. 16
17. Dr. Joe Hages Contact Info E-mail: [email protected] Skype:
joe_hage Web: www.joe.me LinkedIn:
http://www.linkedin.com/in/joehage Twitter:
http://twitter.com/DrJoeHage Facebook:
http://facebook.com/DrJoeHage Amazon:
http://www.amazon.com/author/joe-hage 2008-2014. Copyright, Dr. Joe
Hage. Proprietary Information. All Rights Reserved. 17