<...> means average. The symbol # means "number". So "<time>" means "average [life]time" (in ps) and "# events" means "number [of] events", ie how many times this hydrogen bond was formed. I do not know exactly what the maximum number of the occupancy would be since it depends on how many simultaneous hydrogen bonds that particular atom can form; the summary is not per residue. The final numbers are the averages over all selected donors/acceptors over the whole trajectory. Check corman.doc.