Glenn is starting an annuity, into which he plans on making monthly payments, to save money for his new-born daughter to go to college. He figures he can get an average of 6% compounded monthly on his money. How much should his payments be to have enough to fund his daughter to attend Ivy Tech for 4 years (estimated annual cost $18,000) if he starts saving as soon as she is born and gives her all the money for college when she is 18 years old.