I have difficulty understanding comma usages in the following sentences:
- Mr Hirai had already announced that Sony's TV production goal would be halved, from 40m units to 20m. (The Economist)
Why is the comma placed after "halved?" In the following sentence, which is also from a British newspaper, no comma is used:
As reported, the charge for crossing the bridge will be halved from £3 to £1.50 for cars.
-2. And while unemployment is a modest 6.4% and declining, inflation has picked up sharply, to an estimated 6.5%, more than a point higher than last year. (The Wall Street Journal)
Is the comma after "sharply" necessary? What the difference in nuance with and without the comma?
-3. The government of Prime Minister Naoto Kan has proposed doubling, to 20%, the tax on capital gains and dividends. (The Wall Street Journal)
Why is "to 20%" set off by the commas?
Could anybody shed light on these comma usages?