benchmark, date, observer, organization, receiver, receiver_sn, receiver_type, antenna, antenna_sn, dome, height (m), slant height (m), interval, first_observation (s)
 m504 leveling_benchmark_in, 1996-09-05,  UC BERKELEY ,   ,  TRIMBLE 4000SSE,  5689,  7.15,  TRM14532.00,  103,  NONE, 1.029, 0, 30, 173330
 m504 leveling_benchmark_in, 1999-07-28,  UC BERKELEY ,   ,  TRIMBLE 4000SSI,  16301,  7.29,  TRM29659.00,  66596,  NONE, 1.1751, 0, 30, 1680
 m504 leveling_benchmark_in, 2004-06-02,  Parker ,  USGS ,  TRIMBLE 4000SSI,  16325,  NP,  TRM29659.00,  66915,  NONE, 1.3067, 0, 0, 15520
 m504 leveling_benchmark_in, 2004-06-06,  MPP ,  USGS ,  ASHTECH Z-XII3,  932,  CC00,  ASH701945C_M,  803,  NONE, 1.1258, 0, 0, 161130
 m504 leveling_benchmark_i, 1996-09-04,  UC BERKELEY ,   ,  TRIMBLE,  5689 ,  4000SSE 7.15,  TRM14532.00,  103,  NONE, 1.0536, 0, 30, 16500
 m504 leveling_benchmark_i, 1996-09-06,  UC BERKELEY ,   ,  TRIMBLE,  5689 ,  4000SSE 7.15,  TRM14532.00,  103,  NONE, 0.9276, 0, 30, 1720
 m504 leveling_benchmark_i, 1999-07-27,  UC BERKELEY ,   ,  TRIMBLE,  16301 ,  4000SSI 7.29,  TRM29659.00,  66596,  NONE, 1.2221, 0, 30, 162630
 m504 leveling_benchmark_i, 1999-07-29,  UC BERKELEY ,   ,  TRIMBLE,  14631 ,  4000SSI 7.29,  TRM29659.00,  73545,  NONE, 1.2302, 0, 30, 164030