POSC License Agreement
This file is distributed under the POSC License Agreement at
http://www.posc.org/about/license.shtml.
Use of this file constitutes agreement with the POSC License Agreement.
<xsd:documentation>Grid Correction (Meridian convergence). The angle between
True North and Grid North. Grid Correction is positive when True North
is west of Grid North. The correction is added to the raw observation,
thus yielding a reduced or corrected observation that can go into
the subsequent calculations.</xsd:documentation>