The bar chart compares the estimated daily oil production capacity, measured in millions of barrels, across six countries between 1990 and 2010.
Overall, oil output rose in nearly all countries over the 20-year period, with Saudi Arabia consistently producing the largest amount by a considerable margin, while Qatar remained the smallest contributor. Iraq, Kuwait, and the UAE followed a similar pattern of moderate growth, whereas Iran showed a steady but slightly stronger increase.
In 1990, Saudi Arabia produced just above 8 million barrels per day, already leading the group. Its production expanded continuously, almost doubling to around 14 million barrels in 2010. By contrast, Qatar’s figures were negligible throughout, staying below 1 million barrels despite a minor rise in 2000.
The other nations recorded more modest gains. Iran grew steadily from about 3 million barrels in 1990 to over 4 million in 2010. Iraq and Kuwait both began at around 2 million barrels and nearly doubled their output by the end of the period. Similarly, the UAE rose gradually from roughly 2 million to just under 4 million barrels per day.