We have talked earlier about domain age, since links are playing a vital role in the google ranking process; we should have a look on the key factors that determine the value of a link with regards to its contributions and age. The age of a link is supposed to equate to trust as a link gains weight with age, established credibility and other factors. Anyway, if we loose an older link, we should contact them to get it again, although you may find problems in the restructuring of those links pages.
In order to justify your index page count and presence in google you need to restore them. The longer your links have been on a web page the higher their value. Most of the search engines have an algorithm that determines which links are more valuable than others; you need to build a valuable linking structure that adds weight to age gradually.