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I'm planning a trip from Europe to USA, that will happen next summer.
I was looking lately into purchasing plane tickets, but a lot of carriers do not offer late July/early August 2015 tickets yet.
So, I can buy some ticket on kayak.com, but I feel that if I'll wait a bit, I might get a better deal. My question is generally - when is the best moment to purchase tickets - one that gives best prices, but also doesn't limit available flights too much, so I have options to choose from.