anchor.diff:  "EST","EE","Estonia",2010,1,1
   "EST","EE","Estonia",2011,0,0
   "EST","EE","Estonia",2012,4,0
  -"EST",NA,"Estonia",2013,NA,0
  +"EST","EE","Estonia",2013,NA,0
   "FIN","FI","Finland",1975,NA,NA
   "FIN","FI","Finland",1976,3,3
   "FIN","FI","Finland",1977,2,2
  
positive.code: "NLD","NL","Netherlands",2010,0,0
  "NLD","NL","Netherlands",2011,3,3
  "NLD","NL","Netherlands",2012,2,0
  "NLD",NA,"Netherlands",2013,NA,3
  "POL","PL","Poland",1975,NA,NA
  "POL","PL","Poland",1976,NA,NA
  "POL","PL","Poland",1977,NA,NA
  
negative.code: "IRL","IE","Ireland",2010,2,2
  "IRL","IE","Ireland",2011,1,0
  "IRL","IE","Ireland",2012,4,4
  "IRL","IE","Ireland",2013,NA,3
  "ITA","IT","Italy",1975,NA,NA
  "ITA","IT","Italy",1976,0,0
  "ITA","IT","Italy",1977,4,4
  