I received my HRV device yesterday and it says that a high HRV is good and a lower one may be an indication of something wrong. When we stimulate our vagus nerve its to make the HRV lower, so how do we judge what a good HRV number is? and also does age affect the HRV? is there some sort of chart to refer to, if it does? I'm 55 and it seems like my high and low scores are 48 to 30.