very odd disclosure by nab mlc

NAB/MLC announced that during the period FROM 4 August 2008 TO 7 August 2007 yes thats a seven, thats what they wrote on the form,

they bought 2.9 million shares at prices between 1.61 and 3.14 and they sold 4.2 million shares at prices between 1.61 and 3.14


Now $1.61 to $3.14 would appear to cover the entire trading range of this stock during the past 12 months. So it is entirely uninformative as to when they were actually trading and what they were paying.

It seems to me, clarification is required as to how companies required to file these substantial shareholder notices fill them in, there is very wide variation.