From this article http://www.stproperty.sg/articles-pr...rices/a/159311, it says
"In Singapore, housing in and around the CBD also enjoys an extremely high location premium.
For example, for the period 2002-2012, the price of a private resale flat in Clementi was on average about $490 less per square foot than one in River Valley, which is about 9km closer to the CBD. Resale prices were even lower in Choa Chu Kang, which is an additional 5km farther away from the CBD than Clementi and nearly $625 less per square foot than in River Valley."