anchor.diff:  Snaith,SNI
   Snodland,SDA
   Snowdown,SWO
  +Soham,SOJ
   Sole Street,SOR
   Solihull,SOL
   Somerleyton,SYT
  
positive.code: Kingswood,KND
  Kingussie,KIN
  Kintbury,KIT
  Kirby Cross,KBX
  Kirk Sandall,KKS
  Kirkby (Merseyside),KIR
  
negative.code: Bournemouth,BMH
  Bournville,BRV
  Bow Brickhill,BWB
  Bow Street,BOW
  Bowes Park,BOP
  Bowling,BWG
  Box Hill & Westhumble,BXW
  