Basically, yes, because you'll likely be on reserve your first year, depending on what plane you're going to.
Also, while you're in training you're on Entry-Level Pay, which is lower. It was $2750 a month, but has gone up the same percentage as the other pay rates since 12/31/2008.
So, while you might be busier in the summer and fly more than 70, you'll make less in training. So, it sorta washes out.