what is going on?  the difficultly on the yimp pool has going to almost zero

[2017-09-25 07:13:02] [S/A/T]: 4/13780/13808, diff: 0.136, 189.16MH/s yes!
[2017-09-25 07:13:02] [S/A/T]: 4/13781/13809, diff: 0.136, 189.16MH/s yes!
[2017-09-25 07:13:02] [S/A/T]: 4/13782/13810, diff: 0.136, 189.16MH/s yes!
[2017-09-25 07:13:02] [S/A/T]: 4/13783/13811, diff: 0.136, 189.16MH/s yes!
[2017-09-25 07:13:02] [S/A/T]: 4/13784/13812, diff: 0.136, 189.16MH/s yes!
[2017-09-25 07:13:02] [S/A/T]: 4/13785/13813, diff: 0.136, 189.16MH/s yes!
[2017-09-25 07:13:02] [S/A/T]: 4/13786/13814, diff: 0.136, 189.16MH/s yes!

work is flying by at light speed!