Unsold at 2 keys:

http://www.tf2outpost.com/trade/11096721 - 4 hours

http://www.tf2outpost.com/trade/11096580 - 4 hours

http://www.tf2outpost.com/trade/11090261 - 9 hours

http://www.tf2outpost.com/trade/11089235 - 9 hours (selling 2)

http://www.tf2outpost.com/trade/11085662 - 11 hours

http://www.tf2outpost.com/trade/11082840 - 13 hours

http://backpack.tf/classifieds/id/76561198026315945 - 15 hours

http://backpack.tf/classifieds/id/76561197987904123 - 16 hours

http://www.tf2outpost.com/trade/11078325 - 17 hours

http://www.tf2outpost.com/trade/11078397 - 17 hours

http://backpack.tf/classifieds/id/76561198047934759 - 1 day

http://www.tf2outpost.com/trade/11072731 - 1 day (selling 2)

http://bazaar.tf/trade/229437 - 1 day

http://www.tf2outpost.com/trade/11063918 - 1 day

http://www.tf2outpost.com/trade/11058779 - 1 day

http://www.tf2outpost.com/trade/11058191 - 1 day

http://www.tf2outpost.com/trade/11057302 - 1 day

http://www.tf2outpost.com/trade/11054583 - 1 day

http://www.tf2outpost.com/trade/11058191 - 1 day

http://www.tf2outpost.com/trade/11058779 - 1 day

http://backpack.tf/classifieds/id/76561198055997432 - 2 days

http://www.tf2outpost.com/trade/11018053 - 2 days

http://backpack.tf/classifieds/id/76561198080803822 - 3 days

http://backpack.tf/classifieds/id/76561197973015400 - 3 days

http://www.tf2outpost.com/trade/10985054 - 3 days

http://www.tf2outpost.com/trade/11011547 - 3 days

http://www.tf2outpost.com/trade/11015953 - 3 days

http://www.tf2outpost.com/trade/10989139 - 3 days

http://www.tf2outpost.com/trade/10959835 - 4 days

http://www.tf2outpost.com/trade/10974675 - 4 days (selling 2)

http://www.tf2outpost.com/trade/10900123 - 5 days

http://www.tf2outpost.com/trade/10938374 - 5 days

http://www.tf2outpost.com/trade/10881488 - 6 days

http://www.tf2outpost.com/trade/10791933 - 1 week

http://www.tf2outpost.com/trade/10695092 - 1 week

http://www.tf2outpost.com/trade/10846130 - 1 week

http://www.tf2outpost.com/trade/10728445 - 1 week

Unsold at less than 2 keys:

http://www.tf2outpost.com/trade/11042875 - 1 Robocrate Key (2 days)

http://www.tf2outpost.com/trade/10886933 - 1 key 3 ref (6 days)

http://backpack.tf/classifieds/id/76561198045793604 - 1.5 keys (2 days)

http://www.tf2outpost.com/trade/11081159 - 1.6 keys, selling 2 (14 hours)

http://backpack.tf/classifieds/id/76561197966062569 - 8.88 ref/1.74 keys (18 hours)

http://www.tf2outpost.com/trade/11075152 - 1.8 keys (20 hours)

http://www.tf2outpost.com/trade/10988191 - 1.8 keys (3 days)

Other:

http://www.tf2outpost.com/trade/11074525 - 1 key 1 ref (sold)

http://www.tf2outpost.com/trade/11071551 - 7 refined (sold)

http://www.tf2outpost.com/trade/11039192 - 1 key 3 ref / 8 ref (sold)

http://www.tf2outpost.com/trade/11045872 - 1 Robcrate Key each (sold)

Evaluation:

Based on this proof, 2 keys should no longer be in the range. As for the new price, it is hard to decide. It should not quite drop down to the previous 1.5 key price, and a round figure of 1.6 or 1.8 should be used, anyway, due to keys = 5 refined (.2 = 1 refined). Note: DON'T CHANGE THE KEY PRICE!

Therefore, I've settled with a range of 1.6-1.8 keys for now, since there are sellers in that range. The "Others" section were just some quicksells.