anchor.diff:  Mark,Network,Igs,Name,Latitude,Longitude,Elevation,Datum,Start Date,End Date
  -2406,CG,no,C KAIAPO TLP,-38.691851135,175.994779449,442.788,NZGD2000,2012-02-13T00:00:00Z,9999-01-01T00:00:00Z
  +2406,CG,no,C KAIAPO TLP,-38.691850987,175.994779478,442.776,NZGD2000,2012-02-13T00:00:00Z,9999-01-01T00:00:00Z
   AHTI,CG,no,Ahititi,-38.411447554,178.046002897,563.221,NZGD2000,2009-01-01T00:00:00Z,9999-01-01T00:00:00Z
   AKTO,CG,no,Akitio Station,-40.53980682,176.46122191,432.94,NZGD2000,2006-04-27T00:00:00Z,9999-01-01T00:00:00Z
   ANAU,CG,no,Anaura Bay,-38.268212852,178.291223348,229.304,WGS84,2010-10-18T00:00:00Z,9999-01-01T00:00:00Z
  -ARTA,CG,no,Aratiatia Dam,-38.61758168,176.136412112,369.723,NZGD2000,2008-11-05T00:00:00Z,9999-01-01T00:00:00Z
  +ARTA,CG,no,Aratiatia Dam,-38.617584507,176.136411989,369.654,NZGD2000,2008-11-05T00:00:00Z,9999-01-01T00:00:00Z
   ATIA,XX,no,Aratiatia Dam,-38.61757094,176.1364247,369,NZGD2000,2006-10-12T00:00:00Z,2006-11-08T00:00:00Z
   AUCK,LI,yes,Whangaparaoa No 3,-36.60284464646,174.83438545588,132.6808,NZGD2000,1995-09-18T00:00:00Z,9999-01-01T00:00:00Z
   AUKT,GN,no,Auckland Tide Gauge,-36.8437546,174.7704204,40.1,WGS84,2009-09-22T00:00:00Z,9999-01-01T00:00:00Z
  -AVLN,CG,no,Avalon Sound Stage,-41.196440847,174.932860198,39.552,NZGD2000,2006-02-24T00:00:00Z,9999-01-01T00:00:00Z
  +AVLN,CG,no,Avalon Sound Stage,-41.1964409,174.932860243,39.556,NZGD2000,2006-02-24T00:00:00Z,9999-01-01T00:00:00Z
   BHST,CG,no,Black Hill Station,-39.489184001,176.063174364,882.479,NZGD2000,2008-06-12T00:00:00Z,9999-01-01T00:00:00Z
   BIRF,CG,no,Birch Farm,-40.67976734,176.24610828,308.983,NZGD2000,2005-01-26T00:00:00Z,9999-01-01T00:00:00Z
   BLUF,LI,no,Bluff,-46.58506442275,168.29208660838,124.6401,NZGD2000,2004-03-05T00:00:00Z,9999-01-01T00:00:00Z
   BM8A,XX,no,8A Balmoral Lane,-43.557364295,172.732502262,37.65,WGS84,2013-01-29T00:00:00Z,2016-05-06T00:00:00Z
   BNET,SA,no,Burnett Rock,-43.862486612,170.190142352,757.772,NZGD2000,2005-02-15T00:00:00Z,9999-01-01T00:00:00Z
  -BTHL,CG,no,Battery Hill,-41.340489746,175.136541284,78.839,NZGD2000,2009-01-13T00:00:00Z,9999-01-01T00:00:00Z
  +BTHL,CG,no,Battery Hill,-41.340489736,175.13654136,78.843,NZGD2000,2009-01-13T00:00:00Z,9999-01-01T00:00:00Z
   CAST,CG,no,Castlepoint Station,-40.90981771,176.20155589,173.636,NZGD2000,2006-02-08T00:00:00Z,9999-01-01T00:00:00Z
   CHAT,LI,yes,Chatham Island,-43.95578691377,-176.56583894993,57.9738,NZGD2000,1995-10-04T00:00:00Z,2012-05-23T00:00:00Z
   CHTI,LI,yes,Chatham Island North,-43.73547652045,-176.61711024009,75.678,NZGD2000,2007-12-10T00:00:00Z,9999-01-01T00:00:00Z
   CKID,CG,no,Cape Kidnappers,-39.65787439,177.07635309,234.903,NZGD2000,2006-05-23T00:00:00Z,9999-01-01T00:00:00Z
   CLIM,CG,no,Mt. Climie,-41.14466931,175.14547309,830.724,NZGD2000,2005-10-18T00:00:00Z,9999-01-01T00:00:00Z
  -CLRR,CG,no,Clarence River,-42.144605449,173.815394015,922.9363,WGS84,2017-02-12T00:00:00Z,9999-01-01T00:00:00Z
  +CLRR,CG,no,Clarence River,-42.144610795,173.815401243,922.939,NZGD2000,2017-02-12T00:00:00Z,9999-01-01T00:00:00Z
   CLS3,XX,no,92 Richmond Hill Road,-43.5715,172.757,96,NZGD2000,2011-06-21T00:00:00Z,2015-09-22T00:00:00Z
   CLS4,XX,no,80 Richmond Hill Road,-43.57,172.7578,68,NZGD2000,2011-06-21T00:00:00Z,2011-10-30T00:00:00Z
   CLS5,XX,no,8 Kinsey Terrace,-43.5652,172.7521,70,NZGD2000,2011-06-21T00:00:00Z,2016-04-26T00:00:00Z
   CLS6,XX,no,Clifton Hill,-43.56565764,172.753279407,75.183,WGS84,2011-10-13T00:00:00Z,2016-08-28T00:00:00Z
   CLSG,XX,no,Glendevere Terrace Redcliffs,-43.5601,172.7325,85.7,NZGD2000,2011-03-02T00:00:00Z,2011-06-21T00:00:00Z
   CLSK,XX,no,Kinsey Terrace Sumner,-43.5658,172.7527,89.1,NZGD2000,2011-03-02T00:00:00Z,2017-06-29T00:00:00Z
  -CMBL,CG,no,Cape Campbell No. 2,-41.74901944,174.213817058,257.0051,NZGD2000,2003-12-03T00:00:00Z,9999-01-01T00:00:00Z
  +CMBL,CG,no,Cape Campbell No. 2,-41.749024717,174.21382531,257.273,NZGD2000,2003-12-03T00:00:00Z,9999-01-01T00:00:00Z
   CNCL,SA,no,Conical Hill,-43.6662293,169.8558523,1222.3078,WGS84,2000-02-05T00:00:00Z,9999-01-01T00:00:00Z
   CNST,CG,no,Carnagh Station,-38.48796629,178.211143529,242.6788,NZGD2000,2007-02-22T00:00:00Z,9999-01-01T00:00:00Z
   CORM,LI,no,Coromandel,-36.8654332928,175.74955731881,170.2417,NZGD2000,2003-05-09T00:00:00Z,9999-01-01T00:00:00Z
  
positive.code: OROA,CG,no,Oueroa,-40.10435506,176.68067166,279,WGS84,2010-11-08T00:00:00Z,9999-01-01T00:00:00Z
  OTAK,CG,no,Tuapaka Z,-40.816546002,175.170413249,245.0853,NZGD2000,2007-03-07T00:00:00Z,9999-01-01T00:00:00Z
  OUSD,GN,no,Otago University Survey Department,-45.86950159423,170.51092025742,26.1568,NZGD2000,1995-01-16T00:00:00Z,9999-01-01T00:00:00Z
  PAEK,CG,no,Paekakariki Hill,-41.02176626,174.95208121,443.238,NZGD2000,2003-03-22T00:00:00Z,9999-01-01T00:00:00Z
  PAKI,CG,no,Pakihiroa,-37.89398,178.0826,828,WGS84,2010-06-22T00:00:00Z,9999-01-01T00:00:00Z
  PALI,CG,no,Cape Palliser,-41.569229573,175.25478278,624.147,NZGD2000,2007-02-12T00:00:00Z,9999-01-01T00:00:00Z
  PARI,CG,no,Paritu Road,-38.92257263,177.883276367,507.4359,NZGD2000,2007-02-24T00:00:00Z,9999-01-01T00:00:00Z
  
negative.code: HAAS,LI,no,Haast,-44.07320551218,168.78555264686,1053.549,NZGD2000,2004-06-22T00:00:00Z,9999-01-01T00:00:00Z
  HAMT,LI,no,Hamilton,-37.80675540866,175.10919825195,69.4004,NZGD2000,2003-05-13T00:00:00Z,9999-01-01T00:00:00Z
  HANA,CG,no,Hangaroa,-38.686822718,177.569366285,574.0468,NZGD2000,2007-02-26T00:00:00Z,9999-01-01T00:00:00Z
  HANM,CG,no,Hanmer Basin,-42.552839707,172.792795791,321.647,NZGD2000,2014-05-07T00:00:00Z,9999-01-01T00:00:00Z
  HAST,LI,no,Hastings,-39.61703293042,176.72656394564,152.3338,NZGD2000,2002-09-19T00:00:00Z,9999-01-01T00:00:00Z
  HIKB,LI,no,Hicks Bay,-37.56104136669,178.30335250666,107.2888,NZGD2000,2003-05-01T00:00:00Z,9999-01-01T00:00:00Z
  HOKI,LI,no,Hokitika,-42.71290754419,170.98431530674,53.6686,NZGD2000,1998-06-01T00:00:00Z,9999-01-01T00:00:00Z
  