SHRM (Society for Human Resource Management) references the hard and soft costs of turnover. This is the hard costs category.

This can really climb. Consider the annual salary of the employee(s) who will be utilized to train and support the new hire. Now, consider to regain the productivity and knowledge of the former high-performing employee you are likely looking at a minimum of 1 year. 

Gallup reports that disengaged employees can lead to a loss of 34% of their annual salary in productivity - these are your other  workers covering during the turnover. If they earn $40K also, the loss begins at $13,600.  Some of your soft turnover costs

The Work Institute's Retention Report supports the conservative estimate of $50K or more when factoring in hard and soft costs

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