Researching this issue further, fixed line voice minutes (not the same as duration obviously) have been cannbalised by the existance of mobile phones - no surprises there.
This interesting bar chart from the Economist from Hanging up - Reports of the death of the phone call are greatly exaggerated.
Notice that voice consumption - regardless of device - is dropping. The Economist's report notes that this decrease is matched by an explosion in texting. In the future, I anticipate that we shall look back and see that voice and texting have been in decline since 2010 as communication via data mushrooms.
See also this from Ofcom's The Communications Market Report from July 2012 from James Thickett, Ofcom's Director of Research:
'Our research reveals that in just a few short years, new technology has fundamentally changed the way that we communicate. Talking face to face or on the phone are no longer the most common ways for us to interact with each other.
'In their place, newer forms of communications are emerging which don't require us to talk to each other especially among younger age groups. This trend is set to continue as technology advances and we move further into the digital age.'In short, the arrival of each new generation of technology impacts incumbent technology and after a short period of innovation and experimentation, users work out the most efficient / optimal new mix of technologies at their disposal.'
The new kid on the block - 4G
I remain concerned about the potential success of 4G - there is the need for the quantity of data being transmitted, but I don't see the need for the speed. And Network operators do need to do a much better job of data pricing. As I have mentioned before (see Orange (at last) has a common sense data plan) unlimited policies provide no upper ceiling and are open to abuse. And abuse by 1% will account for a disproportionate cost of serving that content (ie video!).