A computer-implemented method, according to one embodiment, includes: determining which of a plurality of fingerprints correspond to a copy of user data stored in one or more logical volumes at a storage location, and which of the plurality of fingerprints correspond to a pointer that points to a copy of user data stored in the one or more logical volumes at the storage location. A number of unique fingerprints is determined, and a number of the copies of user data stored in the one or more logical volumes is determined. The number of the copies of user data and the number of unique fingerprints are used to calculate an actual deduplication efficiency value. The number of the copies of user data and the number of unique fingerprints are used to calculate a potential deduplication efficiency value. The actual deduplication efficiency value is compared to the potential deduplication efficiency value.