Source of graph: online version of the WSJ article quoted and cited below.
(p. A1) The gap between what Americans and the rest of the world pay for sugar has reached its widest level in at least a decade, breathing new life into the battle over import quotas that prop up the price of the sweet stuff in the U.S.
For years, U.S. prices have been artificially inflated by import restrictions designed to protect American farmers. That has kept the price well above the global market.
But in recent days, the difference between the two has ballooned, giving new impetus to U.S. sugar processors and confectioners to step up their long campaign to pressure the government to increase import limits.
Attention to sugar prices, and the dwindling supply of sugar left in U.S. warehouses, has intensified in the lead up to April 1, after which the U.S. Department of Agriculture can review and change the import quotas, which now stand at 1.3 million metric tons.
Sugar users have long been vocal critics of the quotas but have failed to convince the government to change the limits. The quota has remained unchanged since it was first imposed in 1990, except for two temporary increases after Hurricane Katrina in 2005 and a major refinery explosion in 2008.