Component

2006.5

2007.5

2008.5

2009.5


dX/dt (nT/year)

3.7

4.3

4.2

10.1

dY/dt (nT/year)

6.6

3.8

3.2

3.7

dZ/dt (nT/year)

5.8

4.1

4.3

8.0

 These differences were computed using 684 data points over the modelled area. The secular variation values were computed by getting the change of the field between two consecutive epochs of 1 year interval (e.g. epochs 2006.0 and 2007.0 were used to get secular variation values at 2006.5 epoch)