What should I charge for voice acting?

I've been meaning to get into voice acting, and I'm wondering what would be a good rate for a first time voice actor for recording an IVR phone system?|||Until you've had professional training, and have a good reputation, you'll probably have to work for free, or just expenses, for a long time! Any offer of pay is great, but like ordinary actors, you may have to work for years without payment before anyone will actually employ you for money!