Looking at the list of workloads in our grocery example, you’ll notice that the Clerk has the most time-independent tasks. He only has one time-dependant task which is to answer customer questions. Although it is a valid task that should be part of a job description, it can’t really add significant workload to that person. A question will take much less than one minute and you may have one for each 50 customers that come in. Therefore, the Clerk workload could be considered a time-independent workload altogether.
Since this workload is not tied to a particular time of the day, a planner still needs to evaluate and put time on each task. The trick is to represent that work in the form of hours per day. So if you evaluate each task and sum them, you may end up with 5 hours per day for example. This sum may also change per day of the week. There may not be any delivery truck to unload on Sundays. Therefore, the Clerk workload will have a lower sum on that day.
This will bring you to different sums on each weekday. Figure 2 shows an example of these sums.
Figure 2. Time-independent workload
You will also find that even though this work is more regular, it is exposed to seasonal trends just like the cashier workload. This clerk will be stocking shelves more often during Holiday Season.
Some industries like healthcare transform the number of hours into Full-Time Equivalent (FTE). So if a full-time employee usually has an 8-hour shift, the sum of hours within the day would be divided by 8 in order to get to a number of employees per day. With this approach, the planner now only needs to compare the number of employees scheduled vs. trying to add the scheduled hours.
Although the time-independent tasks are not relative to a time of day, a planner may elect to choose a resolution. That day represents the recurring or resolution time selection, just like the time-dependant workload. Some industries divide the day into pre-determined shifts and indicate the number of hours (or FTEs) required in each part of the day. Manufacturing and Healthcare industries usually have this type of pre-determined cut down of shifts that is equivalent to what employees will receive as shifts. Again, this helps in the process of measuring your schedule. The down side of this approach is the lack of flexibility. As soon as one employee is not working the same shift as what is in the workload, then the planner is back to measuring hours or fractions.
For the expression of workload, it is therefore important to be as precise as can be managed. It is also essential to differentiate the expression of the workload and the measurement of a schedule. The measurement, or coverage, can be more complex that the workload expression and they don’t necessarily need to be linked. Chapter 5 will discuss schedule measures in detail.