Oceania is the most difficult continent to reach, specially the south-central part. These graphs include several different paths, going from the easier ones to Western Australia or the Philippines, to the more difficult to New Zealand or Hawaii. See full graph explanations here.
We missed recently two great Topbanders, who were highly contributing to my Pacific graphs with their dedication and regular daily activity. Very sadly, Mike, VK6HD and Bob, VK3ZL became both Silent Keys.
This graph has been deeply influenced by the recent big and experienced DXpeditions in the Pacific area (and also the growing daily activity of FK8CP and ZL3IX). But the exploit in Spring 2011 is given mainly by VK3PA, worked almost every day.
The same data are condensed in quarterly periods to give a better representation through the solar cycles.