Found a site containing a graph of the equation of time.

If the graph was from yr 1998 will it still be OK to use today. Does the equation of time vary much from year to year?

Thank you

Mike

I'm not quite sure about what you are asking.

Since this is not my area of expertise, I searched Google under the key words "time variation year" to get these possible sources:

http://en.wikipedia.org/wiki/Year
http://www.physics.rutgers.edu/~twatts/sunrise/sunrise.html
http://wvms.nrl.navy.mil/POAM/sh_o3/fig9.html
(Broken Link Removed)

I hope this helps. Thanks for asking.