The ratings here are from the official Chinese rating list issued by Chinese Weiqi Association 3 times a year.
Only the top 30 players are listed here as they are relatively more actively involved in major Chinese tournaments. Their ratings are based on large sample of games and therefore are considered more reliable.
There is no perfect rating system. This rating list should be interpreted wisely. It it probably plausible to conclude that the top 5 players as a team are likely to be very competitive in international team tournaments (such as Nongshim Cup) against Japan and Korea. However, it is probably not reasonable to say that Kong Jie 7p is considerably stronger than Chang Hao 9p simply because Kong's rating is almost 100 points higher than Chang's.