Estimated Next Difficulty: 40,248,405,371 (-0.13%)
I never saw this before:)
The difficulty declined twice last year, one of which was ~this time.
With those two exceptions there was only one other time that the difficulty decreased in the history of bitcoin, although it did stay the same for several months (at "1") in the very early days of mining.
^Had to correct this.
I counted 18 times that the diff decreased on adjustment, just some of that:
8 times in august - november 2011,
4 times in april - may 2012
2 times in december 2012
and once in january 2013