Some sort of high frequency trader algorithm in play here....

Some sort of high frequency trader algorithm in play here. Yesterday little 1 trades down regularly. I noticed 3 times the amount of volume required pop in at the end of trade auction today. (Some of the hidden buyers I guess) A drop down to 19.5 and then 20 before the end of normal trade and reasonably large trades after 4.00 in the auction

	Column 1	Column 2	Column 3	Column 4	Column 5
0	4:10:03 PM	0.200	193,606	38,721.200
1	4:10:03 PM	0.200	200,000	40,000.000
2	4:10:03 PM	0.200	106,394	21,278.800
3	4:10:03 PM	0.200	113,606	22,721.200
4	4:10:03 PM	0.200	7,000	1,400.000
5	4:10:03 PM	0.200	20,500	4,100.000
6	4:10:03 PM	0.200	60,867	12,173.400
7	4:10:03 PM	0.200	39,133	7,826.600
8	4:10:03 PM	0.200	9,867	1,973.400
9	4:10:03 PM	0.200	133	26.600
10	4:10:03 PM	0.200	99,867	19,973.400
11	4:10:03 PM	0.200	1	0.200
12	4:10:03 PM	0.200	532	106.400
13	4:10:03 PM	0.200	4,000	800.000
14	4:10:03 PM	0.200	5,600	1,120.000
15	4:10:03 PM	0.200	9,400	1,880.000

What does this indicate? Something or nothing.