ADDITIONAL.的意思ADA-ES did not say how much activated carbon i

ADDITIONAL.的意思
ADA-ES did not say how much activated carbon is currently produced,but said it expects an additional 400 million pounds a year will be needed by 2010,and up to a billion pounds per year by 2012 to 2015.
是每年再额外增加400MILLION
那么2012到2015年后，每年额外增加1BILLION POUND。增加减少了是吗？