December is typically a slow month because of the holidays. One glance at the stats confirms this simple truth:

But let's take a look at the full year:

Month Page views Visits Visits/day Unique visitors / month Bounce rate Pages / visit Duration
January 2017 495,083 149,904 4,835 80,187 46.56% 3.30 04:52
February 2017 494,576 158,059 5,645 90,684 48.95% 3.13 04:34
March 2017 602,571 185,773 5,896 100,729 47.25% 3.24 04:56
April 2017 531,263 164,103 5,470 90,516 47.51% 3.24 04:51
May 2017 584,353 177,676 5,731 97,492 46.76% 3.29 05:06
June 2017 560,910 166,798 5,560 90,858 45.42% 3.36 05:28
July 2017 561,996 169,019 5,452 93,048 45.52% 3.33 05:25
August 2017 566,470 168,265 5,428 91,916 45.36% 3.37 05:29
September 2017 504,546 146,449 4,881 80,567 44.33% 3.45 05:29
October 2017 517,447 146,962 4,740 79,669 43.19% 3.52 05:33
November 2017 540,264 147,956 4,932 69,690 42.30% 3.65 05:59
December 2017 801,103 130,555 4,211 68,155 13.37% 6.14 08:35

I think there's something wrong with the Bounce Rate and the Pages/Session. That's something to investigate; I think it's caused by redirects from http to https. We'll have to fix this. This doesn't affect other metrics such as the number of visits though, and those were spectacular in 2017:

Statistics for 2017