Hillary Clinton, eight years after first running for president for the first time, still couldn't break through the “highest glass ceiling” to become the first woman elected president in United States history. She was losing to Donald Trump Tuesday after a contentious election season that at times seemed to focus on sexism in a way that hadn’t been seen in modern politics.

Experts note there is still work to be done to reach a level of gender parity — an equal representation between men and women  in public office compared to the population, which is roughly 50-50. From mayors at the local level to state legislatures and the United States Congress, women are significantly outnumbered by men across the country but progress has been made.

“The U.S. has lagged behind many other countries and, right now, we’re at roughly 20 percent” women representation in politics, Sara Angevine, a visiting professor of political science at Whittier College in California, told the International Business Times. “That is not where we aim to be. We’re one of the few industrialized countries who have never had a female in the executive, so this is a big deal in setting the precedent.”

Compared to high income countries around the globe, the United States ranks 33rd out of 49 countries when it comes to women in national legislatures, according to a Pew Research study published last year. And, when compared to a larger group of 137 countries where data was available, the U.S. came in 83rd place.

While women aren’t as represented in American politics compared to those countries, representation has slowly been creeping up, especially in the Democratic Party. Women make up larger shares of national and state lawmakers than ever before, holding roughly 20 percent of the seats in the national House and Senate and between 22 and 25 percent of state legislatures, Houses and Senates, according to data from the Center for American Women and Politics at Rutgers University in New Jersey.

Women representation within lower levels of government — which serve as a training grounds of sorts for politicians before they later seek higher office — is growing but hasn’t reached what is known as critical mass, or a tipping point at which women representation is big enough for them to form effective coalitions, advocate for women's issues and see their numbers boost as a result. When it comes to getting seats in higher offices, one of the main obstacles is the fact that men have held those offices through history. Women, statistically, get elected when running for open seats at similar rates to men, but the vast majority of seats tend to be held by incumbents, a group of people who have extremely high rates of re-election.

“I think the interesting thing is that there’s this tendency to ‘blame’ women for not being politically ambitious enough because what we see is that fewer women are running and there’s a really simple explanation,” Jennie Sweet-Cushman, the assistant director of the Pennsylvania Center for Women and Politics at Chatham University in Pittsburgh, told IBT. “There are all sorts of socialization factors. There are party pressures because they’re predominantly still run by men and they recruit people form their own networks who tend to be men. There are a whole host of factors that influence women’s political ambition and I think that we miss that sometimes.”

Sweet-Cushman noted that, if there is a tendency to blame women for lacking political ambition there’s also a lack of awareness that political representation is so far from eqal.

“If you ask a group of people – which I do at every talk I give – everybody, men and women included, overestimate how many women there are. Nobody thinks that it’s parity but everybody thinks it’s higher than it is,” she said.