Businesses which rely on the valuable work of flexible employees (also known as freelancers, self-employed workers, temp staff or on-demand workers) have to not only face the complexity of their staff planning, but also have to deal with another issue: the size of their employee database. In the industry, this issue is well-known: if there are too many employees on file or in the database, too many of them do not get assigned often enough. As a result, they become frustrated and seek other opportunities outside the company. Thus, they are unavailable when the company actually wants to use them again. On the other hand, if the database is too small, it is always the same employees who are invited to work - which can also lead to frustration - and it often takes considerable effort to find enough people to fill all the roles for an assignment. 

Finding a mathematical solution to the dilemma 

How do you get out of this conundrum? The solution is quite simple: just ask your employees how often they would like to work! In principle, the number of assignable hours your employees are willing to work in total should be around the same as the number of assignable hours which you need on average.

To illustrate this, let us look at a simple sample calculation. We will assume that the average assignment time in your business is 6 hours. Additionally, you know how often your temp workers would like to be assigned per month (e.g. once, three or six times). You also know how many assignment hours you need per year - e.g. 25,000 hours.  

Let's assume your employees prefer to work as follows: 

This means that with the preferences listed above, you need a pool of around 60 employees (temp workers) to account for your yearly assignment hours. You can now add a security buffer to this sample case and raise the number of employees in your pool to 80. However, if you kept a database with only 30 or more than 100 workers, neither you nor your employees would end up being very happy. In the long run, working with self-employed people is successful as long as you can take their needs into account as well.