For years, if the rate went down, Carnival would issue OBC for the difference.
However, some time ago ( I am thinking December 2008 ~ about the same time that Early Saver came out)....Carnival announced that they would not longer discount after the final payment.
Unless you book Early Saver, the price at the final payment is the price you pay.
To be fair, this is why Carnival started offering Early Saver....so that people who wanted the option of getting any price reductions could do so.
So if people want that option, they should book Early Saver.
Personally, I have never understood why people want to book a year out (usually to get the exact cabins they want) and then complain if the price goes down in the last 70 days.
In many cases, the prices go up. If cruisers want a reduction if the price goes down, shouldn't Carnival have the option to charge you MORE if the price goes up?
Cruisers can't have your cake and eat it too.
Once I book a cruise, I am happy with the price I paid or I would not have booked it.
I certainly do not care what everyone else paid for it.