Differences sea-gravity and gravity model (mgal).

BGI data, file data_101011114438.txt:
NUMBER: 4789
0 OBSERVATIONS PREDICTIONS DIFFERENCE ERROR ESTIMATES
MEAND -58.818751 -57.015163 -1.803589
ST.DEVI. 18.224904 17.835087 5.204454
MAX -19.900000 -25.104658 18.457386
MIN -114.300000 -111.229643 -25.915095
NGDB data, file track7562.xyz (reduced so values <> 80 removed:
NUMBER: 83095
0 OBSERVATIONS PREDICTIONS DIFFERENCE ERROR ESTIMATES
MEAND -22.163745 -18.046592 -4.117153
ST.DEVI. 32.126189 21.911666 18.256895
MAX 83.600000 74.659048 79.071035
MIN -179.300000 -111.229643 -79.991061

Update 2014-08-15.