Brent crude oil dropped below $70 a barrel (bbl) on Nov. 9 for the first time since April, officially entering a bear market as losses reached more than 20% since its peak last month.

Traders have rapidly reassessed the state of oil supplies as higher output from the U.S., Saudi Arabia and Russia has overshadowed the start of U.S. sanctions against Iranian exports, sending prices tumbling since Brent hit a four-year high of $86/bbl in early October.