For the world, divide the 10 billion by 86 million to arrive less than four months. "Yes" we need to drill ANWR, but should not be deluded into believing that it is going to save us.
ANWR would probably flow at 1.5 MMBPD after reach peak then likely taper off flowing for more than 30 years.
How do you propose that ANWR be able to produce 20 million barrels per day?