At GE Renewable Energy, we come up with the following business metric to justify the investment for the KM program which is "Cost avoidance in productivity in terms of saved engineering hours and mitigated risks" when reusing solutions to previously solved problems or issues (non-conformance, poor quality,...)
The key elements to enable the calculation are:
1- solve problems. 2- retain your solutions with proper taxonomy, 3- Make the solutions discoverable and searchable (we call it 'critical knowledge finder') 4- measure the reuse or application of these solutions. 5- Recognize and reward the contributors.