The European Commission proposed to increase tariffs on U.S.-made women’s jeans. The commission proposes an increase of 0.45% to 4.3% starting May 1.

The commission has a history of raising and lowering the tariff. The rollercoaster numbers began in May 2013, where the tax was 26 percent, then lowered to 0.35% after May 1, 2014, raised again to 1.5% in 2015, before ultimately being lowers to 0.45% last year.

The added tax to jeans serves as a part of a continuation of sanctions brought forward by the World Trade Organization (WTO) in reaction for the U.S.’s failure to comply with a WTO ruling against the Continued Dumping and Subsidy Offset Act of 2000, also known as the Byrd Amendment. The law gave US the right to distribute antidumping and countervailing duties collected on foreign-made goods to affected domestic industries, according to a Sandler, Travis & Rosenberg press release.

However, the law was later found to violate WTO rules and therefore repealed, allowing distributions to continue for cases before the appeal was established.