UPDATE 1-Oil price to rise only gradually to $80 by 2020 - IEA
* Oil investment to continue decline in 2016
* Middle East share of supply to rise with $50 oil (Updates with comment on investment, releads)
By Amanda Cooper
LONDON, Nov 10 (Reuters) - Oil is unlikely to return to $80 a barrel before the end of 2020 despite unprecedented declines in investment, as yearly demand growth struggles to top 1 million barrels per day (bpd), the International Energy Agency said on Tuesday.
In its World Energy Outlook, the IEA said it anticipates demand growth under its central scenario will rise annually by some 900,000 bpd to 2020, gradually reaching demand of 103.5 million bpd by 2040.
The drop in crude to around $50 a barrel this year has triggered steep cutbacks in production of U.S. shale oil, one of the major contributors to the oversupply that has stripped 50 percent off the price in the last 12 months.
"Our expectation is to see prices gradually rising to $80 around 2020," Fatih Birol, executive director of the IEA, told Reuters ahead of the release of the report.
"We estimate this year investments in oil will decline more than 20 percent. But, perhaps even more importantly, this decline will continue next year as well."
"In the last 25 years, we have never seen two consecutive years where the investments are declining and this may well have implications for the oil market in the years to come." Continuación...