Again, a very interesting article from Olivier Duffez (this time, in English too ;-) about the relationship between the PageRank and the number of Backlinks, and the evolution of this relationship. I’ve already talked about the blog of Olivier here.

Results

The results are presented in the following table. For example the cell corresponding to column 5/2004 and row PR5 shows that in May 2004, an average of 104 backlinks was required to get a PR5.

Conclusion

• With a few exceptions, whatever the PR is, more backlinks than the month before are required every month to get a given PR.
  
• As expected, one needs far more backlinks in order to get a high PR than a low one. Even if there may be exceptions, because the study deals with a good number of data, it gives experimental support to the theoretical hypotheses or ideas never proved before but only discussed in forums.
  
• During this summer (2004), Google changed the behaviour of the link: command which now includes low PR pages. Only PR4 or higher PR pages used to be listed by this command. Conversely since this summer you can also list the low PR pages backlinks, which you can see in the table.