Source:
http://www.eia.gov/countries/img/charts_png/IZ_pettop_img.png
In 1998, the EIA said there'd be a glut of oil worldwide, and the news crashed prices for a year (The only time drilling has stopped completely in this region since oil was discovered in the '50s). Of course, they were wrong, they hadn't taken into account the demand in Asia, but the impact sent a shockwave through the E&P industry that took a year to straighten out.