Unless there is a special "Deal" advertised, we book as early as possible.
Tickerts are sold in blocks...example: There might be 10 seats going for $99 one way...the next 10 seats go for $129..the next 10 for $150..the next 10 $180..and so on and so fourth.
The airlines does this so that they can legally advertise that flights are only $99 one way.
What most people don't realize is that there are only 10 of these seats available.
If you happen to be one of the lucky people who call early enough, you might just GET the cheap seats.
Bottom line...the closer you wait until your departure time to buy them....the more costly the tickets.
Now....Having said that, I have to add that sometimes when business is really slow, the airlines might have a "SALE" in order to fill up a plane, and although you ordered your tickets early, you could possibly have paid more for your tickets than the people who waited until the "SALE"
It's a gamble of sorts.
I can tell you this....from Chicago's Ohare Airport..the flights to Orlando are almost ALWAYS full so they don't have sales very often. That's why I buy MY tickets early.:animwink: