Update WMM model of rfgfs package for magvar().

I am using to calculate magnetic declination


#replaced Sys.Date() with 2019

the O/P is

But in NOAA website using WMM the O/P is
0.14° E ± 0.29° changing by 0.12° E per year

On looking in magvar description it is written that it uses NIMA WMM2005.

Why is there this much variation. Am I using the correct function.
Is there anyway to update the model of magvar()
Or, is there any substitute package for this.

