Life-Cycle of a Personal Network

Definitions
Old Contacts are people you know but don't mix with frequently.

If your Currently Active Contacts exceed 150 to 200, there is a major deterioration in the value of the relationships.

Phase I - Youth
Starting a new activity (life, school, job, home, hobby) everything is ahead of you.

New Contacts are your focus.
Currently Active Contact base: is small but expanding.

Old Contacts: You have few. You relegate people to that status as punishment.

You might be cliquish because you don't have any status but can attain some if you establish yourself in a restricted group.

Phase II - Middle Age
The future holds promise and the past holds allies.

Old Contacts: plentiful and you draw on them when required.
"Well-connected" people find ways to stay connected to Old Contacts.

New Contacts: you are meeting more than you can handle as Currently Active Contacts so you are shoving a lot of them directly into your Old Contact list.

Phase III - Old Age
Old Contacts: these are your focus.
Currently Active Contacts: "alumni" and family.
New Contacts: of little interest.

In terms of the 8 Networking Types.
Stage 1 resembles the Don't Look Back.
Stage 2, the Balanced Networker (but also The Celebrity)
Stage 3, the Complacent Networker