Kansai International Airport Co., Ltd., the company in charge of running KIX announced that on average, the airport sunk 22 centimetres during the year 2000.
Given that the sink continues at the present rate, it is predicted that KIX will stop sinking around the year 2044. It would've sunk between 12.2-15.5metres by then.
These are the PDF files they released in January - in Japanese and not viewable unless you have Japanese Acrobat reader;
What the company wants to say with these data, is that the sinking has been slowing down. The final, total level of sink is not expected to be greater than what they have originally predicted.
Let me take some data from the PDFs. It seems that the predictions were made at the beginning (before KIX opened
Measurement point 17 (inside terminal)
Dec 99 - sunk 13.8m (predicted 13.7m);
Dec 00 - sunk 14.1m (predicted 13.8m);
Predicted to sink 14.1m by 2004, 14.5m by 2044.
Measurement point 9 (inside terminal, near runway side)
Dec 99 - sunk 12.3m (predicted 11.5m);
Dec 00 - sunk 12.5m (predicted 11.5m);
Predicted to sink 11.8m by 2004, 12.1m by 2044.
Measurement point 2 (one end of a runway)
Dec 99 - sunk 9.4m (predicted 9.8m);
Dec 00 - sunk 9.7m (predicted 9.9m);
Predicted to sink 10.0m by 2004, 10.2 m by 2044.
I tried to choose samples that sunk faster, slower and "on-schedule". These data really goes to show that sinking is uneven - different even for two runways that sit next to each other.
for our American readers: 1 foot = 0.305m; 1 inch = 2.54 cm.