A method is disclosed for a method for measuring the availability of a network element or service. For each network element N, a current real availability value CRAV.sub.N and a current time value CTV.sub.N are associated with network element N. Additionally, for each network element N, an operational state value OSV.sub.N is associated with network element N. At a later time, indicated by a new time value NTV.sub.N, a new real availability value NRAV.sub.N for network element N is determined based on the current availability value CRAV.sub.N, the current time value CTV.sub.N, the new time value NTV.sub.N, and the operational state value OSV.sub.N. The new real availability value NRAV.sub.N is stored. Thus, each separate network element N may be associated with a separate real availability value that accurately reflects the availability of network element N specifically, regardless of any availability approximated for network element N's type.