On Sat, 10 Oct 2009 21:23:42 +0100, Dave Liquorice wrote:

> We are buying a variable amount usage, the bit that is measured and
> known, that is *also* charged at variable rates dependant on the time of
> day that that usage is used.

A bit like electricity, if you have off-peak metering.

> (*) Maybe there is an age thing here. I'm of the generation that were
> just being allowed to have electronic calaculators at O Level (four
> function only) and A Levels.

Hah! We had to use four figure tables!

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