Although Bill has nothing saved for retirement so far, he has determined that he will need to have $684,000 in the account when he retires. He plans to open a retirement account and make monthly contributions from his paycheck. The account that earns 6.7 percent annual interest (which is compounded monthly). How much will he have to invest each month to be able to reach his goal at the end of 25 years? Show your answer as a positive number to the nearest penny.