anchor.diff:  CYKF,YKF,71368,Waterloo Well,ON,CA,43.47,-80.39,317,6,cykf
   MMCU,CUU,76225,Chihuahua Intl,,MX,28.7,-105.97,1372,1,mmcu
   CWLT,WLT,71082,Alert,NU,CA,82.5,-62.34,63,5,cwlt
  -KPMD,PMD,72382,Palmdale Productn Flgt Plant 42,CA,US,34.63,-118.08,780,6,kpmd
  +KPMD,PMD,72382,Palmdale,CA,US,34.63,-118.08,780,6,kpmd
   MMTP,TAP,,Tapachula,,MX,14.78,-92.38,29,3,mmtp
   ,,,c11,,,33.6,-99.3,404,7,c11
   ,GDA,74530,Granada Profiler,CO,US,37.77,-102.18,1155,8,p#c
   ,,,lh2,,,44.28,-82.42,177,7,lh2
  -KCRP,CRP,72251,Corpus Christi I,TX,US,27.77,-97.5,14,2,kcrp
  +KCRP,CRP,72251,Corpus Christi Intl,TX,US,27.77,-97.5,14,2,kcrp
   ,,,000293,,,39.99,-122.06,76,7,000293
   ,,,qrz,,,65.41,-164.66,76,7,qrz
   KHOB,HOB,,Hobbs,NM,US,32.69,-103.2,1115,6,khob
  -KAMA,AMA,72363,Rick Husband Amarillo Intl Ap,TX,US,35.23,-101.7,1093,3,kama
  -KFLG,FLG,72375,Flagstaff/Pullim,AZ,US,35.14,-111.67,2134,2,kflg
  +KAMA,AMA,72363,Amarillo Intl,TX,US,35.23,-101.7,1093,3,kama
  +KFLG,FLG,72375,Flagstaff,AZ,US,35.14,-111.67,2134,2,kflg
   ,,,915004,,,8.1,134.7,0,7,915004
   PADQ,ADQ,70350,Kodiak,AK,US,57.76,-152.5,34,5,padq
   ,,,000262,,,30.9,-102.85,917,7,000262
   ,,,bdp,,,69.5,-156.5,96,7,bdp
   ,,,837430,,,-22.9,-43.17,26,7,837430
   MHNJ,,78701,Isla De Guanaja,,HN,16.45,-85.9,15,7,mhnj
  -KMSN,MSN,72641,Madison/Dane Rgnl,WI,US,43.14,-89.33,261,4,kmsn
  +KMSN,MSN,72641,Madison,WI,US,43.14,-89.33,261,4,kmsn
   MHCA,,78714,Catacamas,,HN,14.9,-85.7833333333,442,6,mhca
   KOQT,OQT,,Oak Ridge,TN,US,35.96,-84.29,334,7,o#k
  -KVPS,VPS,72221,Eglin AFB/Valpar,FL,US,30.48,-86.53,26,6,vps
  +KVPS,VPS,72221,Eglin AFB,FL,US,30.48,-86.53,26,6,vps
   KGNR,GNR,72619,Greenville Muni,ME,US,45.462,-69.595,427,7,kgnr
   CYYE,YYE,71945,Fort Nelson,BC,CA,58.84,-122.6,382,5,cyye
   ,,,dsc,,,35.34,-116.88,961,7,dsc
   KHTH,HTH,,Hawthorne,NV,US,38.55,-118.63,1285,8,khth
   K47B,47B,,Eastport,ME,US,44.92,-67.0,23,8,kepo
  -KSNA,SNA,,Santa Ana/John Wayne-Orange Co,CA,US,33.68,-117.87,16,6,ksna
  +KSNA,SNA,,Santa Ana,CA,US,33.68,-117.87,16,6,ksna
   ,,,999370,,,34.8,-120.6,112,7,999370
   KLRD,LRD,72252,Laredo Intl,TX,US,27.54,-99.47,155,3,klrd
  -KSYR,SYR,72519,Syracuse/Hancock,NY,US,43.12,-76.12,127,3,ksyr
  +KSYR,SYR,72519,Syracuse,NY,US,43.12,-76.12,127,3,ksyr
   ,,,000345,,,42.8,-109.81,2163,7,000345
  -KAXN,AXN,,Alexandria/Chand,MN,US,45.87,-95.41,433,3,kaxn
  +KAXN,AXN,,Alexandria,MN,US,45.87,-95.41,433,3,kaxn
   ,,,uhaz,,,64.73,177.5,5,7,uhaz
   ,,,Fort Peck,MT,US,48.31,-105.1,634,7,fpk
   ,,,s#6,,,25.0,-115.0,0,7,s#6
  
positive.code: ,,,c04,,,34.59,-94.3,380,7,c04
  KMLU,MLU,,Monroe Regnl,LA,US,32.51,-92.04,29,6,kmlu
  SEQU,,84071,Quito/Mariscal S,,EC,-0.15,-78.4666666667,2812,6,840710
  KFSD,FSD,72651,Sioux Falls/Foss,SD,US,43.59,-96.74,436,2,kfsd
  KBGR,BGR,72607,Bangor Intl,ME,US,44.81,-68.83,57,3,kbgr
  KMYL,MYL,,Mccall,ID,US,44.89,-116.1,1533,6,myl
  CYEV,YEV,71957,Inuvik,NT,CA,68.3,-133.5,68,5,cyev
  
negative.code: MRLB,,78774,Liberia/Tomas G,,CR,10.6,-85.55,82,6,mrlb
  KMRF,MRF,72264,Marfa Muni,TX,US,30.38,-104.02,1481,6,mrf
  PAVW,VWS,70275,Valdez,AK,US,61.13,-146.35,11,7,pavw
  KEUG,EUG,72693,Eugene,OR,US,44.12,-123.22,114,1,keug
  KLEX,LEX,72422,Lexington,KY,US,38.05,-84.6,300,4,klex
  KLVS,LVS,,Las Vegas,NM,US,35.66,-105.15,2091,3,klvs
  ,,,Franklin,AL,US,32.54,-85.79,157,8,max
  KGZH,GZH,,Evergreen,AL,US,31.42,-87.04,78,7,kgzh
  KIDA,IDA,,Idaho Falls/Fang,ID,US,43.53,-112.07,1453,6,kida
  KLSE,LSE,72643,La Crosse Muni,WI,US,43.88,-91.25,199,6,klse
  