BHCA/subs validation

Hi to all,

I would like to clarify if is it possible to have at BHCA/sub value less than 1 ? if i based it to reality, there is no attempt that will be measured by a less than 1 physical call attempt. but if the value is greater than 1, then it means all the VLR subs are making an attempt and was receiving call. pls advice if I miss on something. thanks you.!