The graph compares changes in the Oil Production Capacity in millions of barrels per day in six countries.
Overall, it is clear that oil production capacity increased in all countries over a period shown However, the most dramatic rise was apparently seen in Saudi Arabia than any of the other countries.
In 1985, Saudi Arabia produced well above 8 millions barrels per day, and this rose significantly to little above 12 million barrels per day in 2005 before soaring its output to just above 14 million barrels per day by the year 2015. In contrast, the lowest oil producing nation was Qatar under 1 million barrel per day throughout the given years although there was a modest increase in 1995.
Oil production capacity in Iran increased gradually from about 3 million barrel per day to well above 4 million barrel per day in 2015. Although the production of oil in UAE, Kuwait and Iraq tended to rise between 1985 and 2015, their production capacities reached under 4 million barrels per day by the year 2015.