I know it gives the graph for the last 4 hours and the current heart rate but what do the 2 numbers mean that are on top of each other? Min over Max over the last 4 hours? Avg over min over the last 4 hours? Min over Max over the last 1 hour? I thought it might be Min over Max over the last 4 hrs but the numbers did not seem to jive in a few cases so now I'm not sure and I can't find an EXACT explanation in the manual.