This is the Relative Name (Rn) of one archived historical sample of the fabric-interconnect switch's CPU-load and memory-usage statistics: the naming fragment that distinguishes this particular SystemStatsHist instance from its sibling instances under the same parent object in the UCS tree. An administrator or a management application appends this Rn to the parent's DN to reconstruct the child's own DN, which matters because SystemStatsHist objects are always addressed relative to whatever they are nested under (a port, a switch, or a monitor). For example, if two SystemStatsHist instances sit under the same parent, only their Rn values differ, so software listing every SystemStatsHist on a fabric interconnect relies on Rn to tell them apart.