* It does not take into account the fact that a small group of
mobile phone subscribers may have changed their telco provider
under the Number Retention Service.
* It also does not take into account the fact that a small group of
fixed line phone users may have bid for a golden number from
exchanges other than the exchange serving their installation
address, and allowed the number to be connected to his local
telephone exchange for a fee of $8 per line per month.
* The 6 Leading Numbers are not entirely accurate due to:
- Some telephone exchanges have since closed down e.g. Yio Chu
Kang, Sembawang.
- There is no way to fix certain geographical locations to a
specific telephone exchange.