CPIM Part 1, Formulas Flashcards
Total production (In a MTO environment + level prod plan)
Total forecast
+
backorders
+
ending inventory
-
opening inventory
Net requirements
Scheduled receipt
-
Prior projected available
Ending projected available balance (PAB) - Not time fences
Beginning PAB
+
Scheduled MPS receipt
-
Demand
New safety stock
Old safety stock
X
√ (New lead time / Old lead time)
Projected available
Prior period projected available
+
Scheduled receipts
+
Planned order receipts
-
Gross requirements
Net requirements with safety stock
Scheduled receipts
-
(Prior period available - safety stock)
ATP for periods containing MPS
Sum of customer orders before next period containing MPS receipt
First period ATP
Sum of customer orders before period containing first scheduled MPS receipt
MAD
Sum of absolute actual - forecast
/
Number of periods
Tracking signal
Algebraic sum of forecast deviations
/
MAD
Ending projected available balance - before demand time fence
Prior period PAB
+
Scheduled MPS receipt
-
Customer orders
Ending projected available balance - after demand time fence
Prior period PAB
+
Scheduled MPS receipt
-
Greater of customer orders or forecast
Break even in units
Fixed costs
/
(price per unit - variable cost per unit)
Ending inventory
Prior period ending inventory
+
Production
-
Demand (forecast)
Seasonal index
Period average demand
/
Average demand for all periods
Rated capacity
Available hours
X
Efficiency
X
Utilization
Utilization
Hours actually worked
/
Available time
Efficiency
Standard hours produced
/
Hours actually worked
Operation time per workorder
Setup time
+
Run time
Demand during lead time
Units per period
X
Lead time
Order point
Demand during lead time (DDLT)
+
Safety stock
Average ordering cost per order
(Fixed cost / Number of orders)
+
Variable costs
Net requirements
Scheduled receipts
-
Prior projected available
Average inventory with safety stock
Q
/
w
+
SS
Demonstrated capacity
Sum of standard hours per time bucket
/
Number of time buckets
Critical ratio
(Due Date - Present Date)
/
Lead time remaining
Planned backlog
Previous planned backlog
+
Planned inputs
-
Planned outputs
Actual backlog
Previous actual backlog
+
Actual input
-
Actual Output
Average inventory
(Inventory at period start + inventory at period end)
/
2
Inventory turnover
Annual COGS
/
Average inventory in dollars
Safety stock
SD or MAD in units
X
Appropriate service factor for SD or MAD
Customer service level
(Orders per period - Stockout chances per period)
/
Orders per period
Cumulative variance (outputs)
Previous cumulative variance
+
Actual output
-
Planned output
Cumulative variance (Inputs)
Previous cumulative variance
+
Actual input
-
Planned input
New forecast
(Exponential smoothing)
(alpha x latest demand)
+
((1-alpha x previous forecast))
Forecasted demand
(deseasonalized)
Seasonal index
X
deseasonalized period forecast
Deseasonalized demand
Period average demand
/
Seasonal index
What is the formula for calculating the target inventory in a periodic review system?
T = D X (R+L) + SS
Demand per period X (review period + lead time) + safety stock
What is the formula for calculating annual carrying costs?
(Q/2) x c x i
average inventory X cost per unit X carrying cost rate
