anchor.diff:  1979/10/8,"Swissair Flight 316","","","",37.87388888888889,23.740833333333335,""
   1979/10/31,"Western Airlines Flight 2605","","","",19.43638888888889,-99.07222222222222,""
   1979/11/15,"American Airlines Flight 444","","","",38.95305555555556,-77.45,""
  -1979/11/26,"PIA Flight 740","","","",undefined,undefined,""
  +1979/11/26,"PIA Flight 740","","","",,,""
   1979/11/28,"Air New Zealand Flight 901","","","",-77.42500000000001,167.45833333333331,""
   1979/12/23,"Turkish Airlines Fokker F28 crashes into a hillside","","","",40.32944444444445,33.15694444444444,""
  -1980/1/21,"Iran Air Flight 291","","","",undefined,undefined,""
  +1980/1/21,"Iran Air Flight 291","","","",,,""
   1980/2/21,"Advance Airlines Flight 4210","","","",33.94611111111111,-151.1772222222222,""
   1980/3/14,"LOT Flight 7","","","",52.18472222222222,20.949722222222224,""
   1980/4/12,"Transbrasil Flight 303","","","",0,0,""
  
positive.code: 1967/7/19,"Piedmont Airlines Flight 22","","","",35.33722222222222,-82.43777777777778,""
  1967/10/12,"Cyprus Airways Flight 284","","","",0,0,""
  1967/11/4,"Iberia Airlines Flight 062","","","",51.05166666666666,-0.6905555555555556,""
  1967/11/6,"TWA Flight 159","","","",undefined,undefined,""
  1967/11/16,"Aeroflot Flight 2230","","","",0,0,""
  1967/11/20,"TWA Flight 128","","","",39.08416666666667,-84.66972222222223,""
  1968/3/6,"Air France Flight 212","","","",undefined,undefined,""
  1968/3/24,"Aer Lingus Flight 712","","","",0,0,""
  1968/4/8,"BOAC Flight 712","","","",0,0,""
  1968/4/20,"South African Airways Flight 228","","","",undefined,undefined,""
  1968/5/3,"Braniff Flight 352","","","",0,0,""
  1968/5/22,"Los Angeles Airways Flight 841","","","",0,0,""
  1968/7/1,"Seaboard World Airlines Flight 253A","","","",0,0,""
  1968/7/3,"1968 BKS Air Transport Heathrow crash","","","",51.473333333333336,-0.45,""
  1968/7/23,"hijack El Al Flight 426","","","",0,0,""
  1968/8/14,"Los Angeles Airways Flight 417","","","",undefined,undefined,""
  1968/9/11,"Air France Flight 1611","","","",43.28527777777778,7.223611111111111,""
  1968/10/25,"Northeast Airlines Flight 946","","","",undefined,undefined,""
  1968/11/22,"Japan Airlines Flight 2","","","",undefined,undefined,""
  1968/12/2,"Wien Consolidated Airlines Flight 55","","","",59.771388888888886,-154.14111111111112,""
  1968/12/12,"Pan Am Flight 217","","","",10.6,-66.95,""
  1968/12/24,"Allegheny Airlines Flight 736","","","",41.76777777777777,-78.60166666666666,""
  
negative.code: 1952/12/6,"Cubana de Aviación Douglas DC-4 crashes","","","",0,0,""
  1953/1/5,"1953 Nutts Corner Viking accident","","","",0,0,""
  1953/2/2,"1953 Skyways Avro York disappearance","","","",0,0,""
  1953/7/12,"Transocean Air Lines Flight 512","","","",,,""
  1953/9/1,"Air France Flight 178","","","",44.29083333333333,6.698888888888889,""
  1953/9/16,"American Airlines Flight 723","","","",42.745,-73.86388888888888,""
  1953/10/29,"BCPA Flight 304","","","",37.405833333333334,-122.325,""
  1954/1/10,"BOAC Flight 781","","","",42.67833333333333,10.427222222222222,""
  1954/3/13,"BOAC Lockheed L-749A Constellation","","","",0,0,""
  1954/4/8,"South African Airways Flight 201","","","",,,""
  1954/7/23,"1954 Cathay Pacific Douglas DC-4 shootdown","","","",0,0,""
  1954/9/5,"KLM Flight 633","","","",0,0,""
  1954/12/25,"1954 Prestwick air disaster","","","",55.50194444444445,-4.573333333333333,""
  