User blog comment:IamJakuhoRaikoben/Sorcerer Magazine, Issue 29: May 2014/@comment-4449950-20140602011710/@comment-2214433-20140602072038

One Piece released only 1 volume this year, while AoT had 2. I'm quite interested to see the ranks at the end of this year, since Oda is getting patched up so hopefully no more extended hiatuses.

As for FT, we're technically looking at 2 and half volumes (half, because last volume went out a week ago) worth sales, so it's not that bad. The sales aren't dropping as you said, it's just that everyone else is selling more, lol.

I'm more surprised that the garbage that Bleach has been releasing this year is still selling so well.

A little bit of (unrelated) trivia: According to the New York rank thingy, Attack on Titan's 1st volume has been in top 10 of best selling manga volumes in the U.S. for 50 weeks in a row.