Holy shit! You can finally see when a listing was created. OMG! MOM, GET THE CAMERA! xD

Classifieds :

https://gyazo.com/0301c5f6deb4a4ed670717f59078a1f0 (gif)

1 at 19 ref (unsold for 8 days, have mobile auth.) | 2 at 1 key (both have mobile auth., unsold for 2 months and 26 days)

Unsold :

http://www.tf2outpost.com/trade/27875147 - 1 key (2 weeks)

Conclusion :

Less than 5% change but keys are closer to 19,66 ref or even 20 ref so this is almost 5%. Not to mention that this thing doesn't sell at all. SCM supports.