With talk of “reciprocal tariffs” and “retaliatory tariffs” dominating the global print economic news, U.S. women are starting to hear more – and say more – about another type of tariff. A sneaky little personal one that has long caused women’s clothing, shoes, and undergarments to cost more than men’s.

It’s termed the “pink tariff” and it’s essentially an equity gap in U.S. trade policy that adds roughly 3% more to the price tag of gendered items in the fashion industry. The left-leaning Progressive Policy Institute produced research that shows the total impact of pink tariffs to be a 2 billion gender surcharge on American women.

Here’s why: Imported manufactured apparel and footwear are assessed tariffs under a U.S. Harmonized Tariff Schedule, or HTS, which sets rates based on categories of merchandise such as gender and fabric content. And because HTS has long set higher rates for women’s clothing, this means that women’s suits in 2017 were assessed a 15.1% tariff compared to 13.3% for men.

It also means that women purchasing lower-priced items or fast fashion are paying more, because luxury items made of silk or cashmere are treated differently under the HTS than are mass-produced made with less costly materials, like nylon or polyester.

Sadly, not even your unmentionables are safe from gendered tariffs. Your panties are subject to a 12.8% tariff while your male colleague’s underwear is only hit with an 8.6% tariff.

And these tariffs may increase in the near future. According to Vogue Business, 98% of clothing purchased in the U.S. is imported; 25% of it from China. So, with the newly announced (albeit ever-changing) tariff schemes, women are likely to bear the highest burden of financial impact when it comes to fashion.

Here’s the crazy thing: there’s no real reason or good explanation for why this tariff gender gap exists.

Most economists say it’s been around since at least the 1980s and can only point to the fact that apparel tariff policy began in earnest during the 1930s-40s, when the textile manufacturing industry was strong in the U.S. – and when the men’s apparel industry was a more dominant economic force than the women’s industry. Tariffs were applied to address imports/exports in men’s clothing, not women’s, and a gender gap simply evolved over time.

And while the U.S. government has plainly recognized the inequity (a 2018 paper by the International Trade Commission detailed the unfair burden), no one’s really paid that much attention to it – until now.

Two U.S. Representatives, Brittany Petterson (D-CO) and Lizzie Fletcher (D-TX), decided to use the uptick in tariff talk and Women’s History Month as timely news hooks for the introduction of the Pink Tariffs Study Act, a bill that would “require the U.S. Department of Treasury to conduct a study on potential gender bias and regressivity within the U.S. tariff system and report the findings to Congress.” (See the full text of the legislation here.)

Their legislation may be Democrat-led but there’s certainly a non-partisan interest in addressing the mystery – and pocketbook pain – of pink tariffs.

“As he is instituting massive new tariffs, President Trump is missing a chance to tackle historically regressive and misogynistic traits” of the global free trade system, said Steve Lamar, the president of the American Apparel & Footwear Association, told CNN.

Some, like Lori Taylor, a Texas A&M University professors who specializes in trade policy, would like to see the all apparel tariffs – pink or otherwise – go away.

“My policy preference would have been to lower tariffs for both men’s and women’s clothing” to reduce the [gender] gap, Taylor said.

What can women in print do to advocate for gender fairness in tariff and trade policies?

Stay informed and communicate to your U.S. Representative that you’re following his or her stance on the “Pink Tariffs Study Act.” It may not be a top-tier policy that’s keeping you up at night, but it’s certainly one that adds up when you look at your closet – and your underwear drawer.