It seems odd, but I just checked the things .. Sony gave PS2 numbers, up until the DS was pretty much done. The last one was 155M till march 2012. And at that time DS was clearly not reaching it. After that they stopped. It's like they want to show that they are ahead, and once they saw that the DS is not a threat they stopped putting exact numbers, just to leave a door out, if in future other system comes close, they could easily announce what the PS2 has done since the last official number - 155M, but at the same time using the time being (those years after 2012) to hide the Vita's failure. And if future system comes close they can go out and say 160M - as now, since PS2 system were selling from march 2012 up until way into 2013.
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