anchor.diff:  "Tanzania",TZ,1992,53.5870387244229
   "Tanzania",TZ,1991,43.715550990298
   "Tanzania",TZ,1990,35.2585360719712
  -"Thailand",TH,2014,12.3383050866591
  -"Thailand",TH,2013,12.3975966339683
  -"Thailand",TH,2012,12.3793249247715
  +"Thailand",TH,2015,12.2167532979014
  +"Thailand",TH,2014,12.3073106881264
  +"Thailand",TH,2013,12.3901681631358
  +"Thailand",TH,2012,12.3785988969072
   "Thailand",TH,2011,12.3703845015087
   "Thailand",TH,2010,12.1699090702333
   "Thailand",TH,2009,11.835393710521
  
positive.code: "China",CN,1992,1.84382495116612
  "China",CN,1991,1.7432480246066
  "China",CN,1990,1.68764208773937
  "Colombia",CO,2014,1184.52879745376
  "Colombia",CO,2013,1180.25850851105
  "Colombia",CO,2012,1175.53571656759
  "Colombia",CO,2011,1161.90989451483
  "Colombia",CO,2010,1111.17044066305
  "Colombia",CO,2009,1082.97923120833
  
negative.code: "Venezuela, RB",VE,1992,0.0175221378466537
  "Venezuela, RB",VE,1991,0.0139745759090283
  "Venezuela, RB",VE,1990,0.0118894747599056
  "Vietnam",VN,2015,7591.6746963041
  "Vietnam",VN,2014,7682.40925176152
  "Vietnam",VN,2013,7532.72755244719
  "Vietnam",VN,2012,7307.62718579315
  "Vietnam",VN,2011,6709.19157781948
  "Vietnam",VN,2010,5647.09854497341
  "Vietnam",VN,2009,5100.24725432988
  