Declination


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                   IGRF-11     observed   difference   
 Epoch  Station   decl.(deg)  decl.(deg)  model-obs.
-----------------------------------------------------

 1981.0   THL       -73.87      -74.35      +0.48
          GDH       -48.08      -48.02      +0.06
 
 1983.0   THL       -73.18      -73.64      +0.46
          GDH       -47.53      -47.46      +0.07
 
 1985.0   THL       -72.52      -73.03      +0.51
          GDH       -46.98      -46.96      +0.02
          NAQ       -33.23      -32.93      -0.30
 
 1987.0   THL       -71.72      -72.33      +0.61
          GDH       -46.33      -46.39      +0.06
          NAQ       -32.73      -32.40      -0.33
 
 1989.0   THL       -70.92      -71.48      +0.56
          GDH       -45.70      -45.79      +0.09
          NAQ       -32.22      -31.87      -0.35
 
 1991.0   THL       -70.00      -70.63      +0.63
          KUV       -55.40      -58.4       +3.0   
          UPN       -51.85      -52.1       +0.25
          UMQ       -46.23      -46.4       +0.2
          GDH       -45.02      -45.17      +0.15
          STF       -40.57      -41.8       +1.2		  
          SKT       -39.50      -40.4       +0.9
          GHB       -37.47      -39.4       +1.9
          FHB       -34.23      -36.5       +2.3
          NAQ       -31.68      -31.37      -0.31
 
 1993.0   THL       -68.97      -69.52      +0.55
          GDH       -44.30      -44.51      +0.21
          NAQ       -31.13      -30.84      -0.29
 
 1995.0   THL       -67.92      -68.17      +0.25
          GDH       -43.58      -43.77      +0.19
          NAQ       -30.60      -30.25      -0.35
 
 1997.0   THL       -66.13      -66.54      +0.41
          GDH       -42.60      -42.91      +0.31
          NAQ       -29.93      -29.60      -0.33
 
 1999.0   THL       -64.33      -64.64      +0.31
          GDH       -41.62      -41.95      +0.33
          NAQ       -29.27      -28.89      -0.38
 
 2001.0   THL       -62.42      -62.65      +0.23
          GDH       -40.58      -40.95      +0.37
          NAQ       -28.58      -28.16      -0.42       
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