This is the lowest value recorded during the current performance-monitoring interval of the accumulated chromatic dispersion measured on this channel during the current performance-monitoring interval, expressed in picoseconds per nanometer (or per picometer for the averaged/min/max readings), reflecting how much the fiber has spread the signal's spectral components apart in time. The lowest dispersion value seen in the interval helps characterize the low end of how much a fiber's dispersion has drifted, for example as ambient temperature changes across the day. For example, seasonal temperature swings on an above-ground fiber route might show up as a gradually shifting chromaticDispersionMin across monthly reports even without any physical change to the fiber.