The Rolling Average HRV displays the average HRV over set duration intervals throughout a measurement while the HRV displays the heart rate variability, scaled ln(rMSSD), for each point and all previous points of the measurement.
The rolling average time interval (i.e. 30s) controls the sample frequency of the rolling average for the chart lines that are labeled “Rolling Avg”.
The average HRV score is 59.3 for Elite HRV users. Being above or below average is interesting to know, but it does not tell you whether your score is “good” or “bad”.