some recent short sales

Just of interest -

short sales of arrow for the past few days.

http://www.asx.com.au/data/shortsell.txt

date total shares sold total short sales % turnover
4/3 3,179,623 475,973 14.96
9/3 68,332,683 9,452,826 13.83
10/3 14,383,397 1,524,069 10.59
11/3 11,526,261 96,244 0.83
12/3 8,124,588 599,660 7.38

Do the shorters of Friday, know something we don't or is this something to do with NAB coming on and off the register?