If you are interested in checking the previous editions we recommend to use "The Internet Archive". Please, take into account that the methodology has evolved substantially during the last decade, so use caution when comparing results from different editions.
It should be noted that the aim of the ranking is to promote Open Access, not to classify websites, so your priority should be to involve everybody in your organization in the generation and publication of web contents and not on the insane task of monitoring the ranks.
This is probably the only useful ranking that allows feasible strategies to be implemented and having impact without wild mergings, wasting huge amounts of funds or expecting Nobel miracles.