I recently was collaborating with some folks over on the Sustainable Asset & Maintenance Management (A&MM) Linkedin page regarding the DPFC and how it is better than just the traditional P-F Cuve. I've listed the relevant post below.
Part 3: The Dynamic P-F Curve. The example of the milk carton emptying can be modeled with our DPFC and the rate of change of the Estimate vs the Forecast P-F Curve. The curve shown in marker on the carton is the Estimated P-F Curve. The reality is that when the boys have a sleep over and there are now 3 boys instead of one drinking from the carton, the original P-F Curve is useless to prevent Functional Failure. The estimates are based upon past history, not current conditions. The volume that is now leaving the carton has changed and therfore, the P-F must also change. IT MUST BE DYNAMIC. This is the basis for our Dynamic P-F Curve.
This post was added as from a Linkedin question to me regarding expiration rather than level. I thought it was a good enough though experiment to add to this post.