Interestingly, the same statistics was commented to be too good to be true in the primary school forum.
You may like to look at a comparison table here:
http://www.edu-kingdom.com/home.php?mod=space&uid=35057&do=blog&id=1881
Most parents consider PKC as a band 2A or band 1C school. Judging from the table, we have done better than expected and I do hope we will get better and better.