I bought 75 "Christmas" collection boxes. This was my haul (not too much Gold as I didn't get duplicates of many tanks... and I got screwed with a lot of 100k credit boxes):
51 Days of Premium
26,000 Gold (not including duplicate tanks gold)
E75 TS x 1
Obj 703 v.II x 1
Sexton I x 2 (2,200 Gold from the duplicate)
Pz.Kpfw. III Ausf. K x 1
Bretagne Panther x 1
Sherman VC Firefly x 1
AM 39 Gendron-Somua x 1
2,900,000 Credits (only 3 of those were 500k credit boxes, the other 14 were 100k)
E100 3D Skin
Jgpz E100 3D Skin
I felt as though I certainly had a much lower haul than previous years. 14/75 boxes only gave me the bonus 100k credits. That's 18%. Considering how many different prizes there were, the 100k credits popped up far too often.
I'm still happy as I managed to get both new premium tanks and I got the unique commander this year as I didn't get it last year. Sadly, the 3D skins I got are both for lines I haven't even started yet. They'll go with my Grille line 3D skin that I haven't started yet either... Was really hoping for the E4, 430u and 140 skins.
On a side note, I did get another 11 "Magic" boxes with the $20 card I won from the Derpsgiving giveaways. It got me the 13 105 3D skin which I do have. No notable hauls. I got another Sexton and the rest was mostly credits or small amounts of Gold.
Sadly, it appears that WG nerfed the drop rates this year. Also, they made the collections almost impossible to complete by increasing the number of ornaments by quite a lot. Tying the credit bonus to the total number of ornaments collected is just petty. Previous years, as soon as you hit tier X festive atmosphere, you had the full 50%. This year, unless you buy a large box from each set, you're likely not going to complete any of the collections or get the 50% bonus to credits.