It has been found that the flight ticket fares change about 62 times on an average over the course of 11 months. With each decrease and increase of the flight ticket tariff being changed, a difference of nearly INR 2,655 is noticed. Studies claim that this is usually how a change in flight ticket prices have been measured. Hence, it is recommended that you make your bookings during the 'Prime Booking Window'. A Prime Booking Window falls between four months to three weeks in advance from the departure date. Basically, between 121 to 21 days is the prime booking window within the traveller should monitor the fluctuations in ticket prices and accordingly fix an attractive price. You will notice that during this period, there will be some tremendous shifts or rather fluctuations of the flight ticket prices.
However, if you're looking at cheap international flight tickets, the best thing to do would be to monitor the fluctuations closely and as soon as a very attractive deal is noticed, go for it. It will help you get the desired price for the flight ticket you've been trying to book. You might even get some additional perks if you snoop around a little more.