Is there a percentage value for fast casting?

Does anyone know it?

I find it pretty lame that Anet tells Elementalists how much Energy Storage does, tells Necros how much Soul Reaping does, tells Warriors how much Strength does, tells Monks how much Divine Intervention does...

But not how much Fast Cast does?

How much faster does my spell cast per each point?

Lol, you've been on this site for a long time and haven't read the big article on fast cast? It's not a linear improvement with each point, so the answer isn't a simple one except that you get a 50% decrease in casting time at 16.

Here you go, since the article will be clearer than anyone's explanation:

http://www.guildwarsguru.com/content...ing-id1177.php