The performance appraisal process is one that is charged with the purpose of evaluating the performance of office processes with regards to their efficiency, quality, quantity, financial cost and time to complete. They are used to give a tangible result to the work performance of the various processes that are involved in the office, showing the training needs of the employees and determining what process needs the different office departments have (Slack et al., 2007: 62). Consider the following two applications that are run by a particular governmental office:
Cycle Time: This is defined as the period that is required in order to complete one cycle of a particular operation or to complete a particular function from the beginning to the end. The cycle time is used to differentiate the total duration of the process from its runtime (Slack et al., 2007: 69). Thus the Cycle Time can be calculated as:
- Cycle Time = the average time it takes to complete a particular task.
=The process with the longest processing time.
= Processing time / Number of operations
- Thus, for input information
Basic: Cycle Time= 60 Applications / 10 Operation = 6
Special: Cycle Time= 140 Applications / 20 Operations = 7
- Verify information
Basic: Cycle Time= 60 Applications / 10 Operation = 6
Special: Cycle Time= 100 Applications / 20 Operations = 5
- Double Check work
Basic: Cycle Time= 20 Applications / 10 Operation = 2
Special: Cycle Time= 60 Applications / 20 Operations = 3
- Mailroom
Basic: Cycle Time= 30 Applications / 10 Operation = 3
Special: Cycle Time= 30 Applications / 20 Operations = 1.5
- Moving between stations
Basic: Cycle Time= 10 Applications / 10 Operation = 1
Special: Cycle Time= 30 Applications / 20 Operations = 1.5
- Totals,
Basic: = 18
Special: =18
Throughput Time: Also referred to as the turnaround time, this is the average time that it takes for one of the office operation units to go through the entire process- from the beginning to the end-including the time that is spent waiting between the sub-processes.
Throughput Time= Sum of all Operation times + Sum of all operations waiting in queue to be processed (Middleton & Hawkins, 1998:9).
More technically,
The throughput time= The sum of all the completion times of the various operations + the sum of the queued processes for that particular application.
For Basic Processes:
Throughput Time= (60+60+20+30+10) + 10 = 190
For Special Processes:
Throughput Time= (140+100+60+30+30) + 20 = 380
Throughput Efficiency: This is the average rate at which successful work is done by the various office processes.
Throughput Efficiency= Operation time ÷ Cycle time
According to these calculations, it is clear that the total cycle times for the two processes are equal. However, the individual times for the two processes are different, with Basic operations having lower cycle times for input information, double-check work, and moving between stations. More effort needs to be put in special operations for the input of information, double-checking of works , and moving between these operations in order to make them more productive. Assuming that there is no more time required for any of the processes, then,
Lead time= cycle time X Units of Work- in-Progress X Number of operations + The Queue time between the operations
Thus, for basic applications,
Lead time= 18 X 4 X 5 + 10 = 370 minutes
For special applications
Lead time= 18 X 7 X 5 + 20 = 650 minutes
Notice how the units of the number of WIP drastically change the lead time of the applications. This is the reason why the managers of the organizations should observe much lean with smaller batches of operations (Middleton & Hawkins, 1998: 12). Time delays in between the operations is observed as a primary contributor of this lead time, often presenting the management of the organization with inequitable chances to quickly eliminate waste.
Reference List
Middleton, V. & Hawkins, R. (1998). Process Management for Dummies. Oxford: Butterworth-Heinemann.
Slack, N., Chambers, S. & Johnston, R. (2007). Operations Management. Oxford: Pearson / Prentice Hall.