The so-called “tampon tax,” the issue Cristina Garcia now finds herself championing, isn’t one she just stumbled upon; the California assemblywoman said she has been thinking about this “gender injustice” for a while.

“I think a lot of women have at some point, thought about it, you know?” Garcia said.

Last year, Garcia kicked around the idea of introducing legislation that would make feminine hygiene products exempt from sales taxes in America’s most populous state.

She didn’t pull the trigger just then. But at a meeting in October, she heard from women in her district, and they talked a lot about their daily struggles and “how it all adds up,” she said.

On average, according to Garcia’s office, women in California pay about $7 per month for 40 years for tampons and sanitary napkins. Statewide, it adds up to more than $20 million annually.

These products, her office said, “are a basic necessity” that should not be taxed; it’s especially “unjust” since the tax only impacts women who are already suffering on the wrong end of the gender wage gap.

And so on the first day of California’s 2016 legislative session, Garcia announced Assembly Bill 1561, which proposed an end to the tampon tax.

“I just want people to realize this is not insignificant,” said Garcia, a Democrat. “Especially if you’re on a tight budget.

“And this is just the first step on a long discussion we need to be having,” she added.

Tampons (and similar products) are tax-exempt in only a handful of states, including Maryland and New Jersey.

“Basically we are being taxed for being women,” Garcia said in announcing the bill. “This is a step in the right direction to fix this gender injustice.”