fizkes/iStock(NEW YORK) -- The end of the 2019 is just over two months away, which means for many workers across the U.S. it's time to write the sometimes dreaded but always important year-end review.

The review is a chance for employees to hype themselves, touting all the good work they've done the past year, but that may be harder for women to do than men, according to new research.

When men and women performed equally on a test, women on average reported their performance as being 15 points lower on the 100-point scale than the average man, according to a study from researchers at Harvard Business School and the Wharton School at the University of Pennsylvania.

The researchers described the results as a "gender gap in self-promotion" and said it could contribute to the gender gaps that exist in education and the economy.

Perhaps the most well-known gender gap is pay, in which a woman earns 80 cents for every dollar earned by a man. That gender pay gap results in $513 billion in lost wages each year for women, according to a report released last year by the American Association of University Women (AAUW), a non-profit organization dedicated to empowering women and girls.

The year-end review is an annual point where women have a chance to step up and demand more pay, which is why it is so important for women to to tout their own successes, experts say.

"Advocating for what they want in a way that is favorably listened to and acted on is a huge challenge for women," said Lauren McGoodwin, 31, founder and chief executive of Career Contessa, an online career platform for women.

"We hear it on everything from a raise or a promotion to maternity leave and accommodations as a parent," she said. "Women say, 'I’ve done it all the ways I’m supposed to and nothing is happening.'"

Women also face institutional barriers, especially when it comes to promotions, a phenomenon known as the "broken rung." For every 100 men promoted to manager, only 72 women are promoted and hired, according to the 2019 Women in the Workplace Report by LeanIn.org and McKinsey & Company.

The key for women when it comes to overcoming career barriers is not to think or act like a man, notes McGoodwin.

"It’s about developing your style and that is a work in progress," she said. "You have to find what works for you because you’re in it for the long game of your career."

Here are five tips for women for nailing the year-end review:

1.Think about it all year:

No matter when your next review meeting with your boss is happening, start thinking about it now.

That includes keeping a record of tasks you take on, congratulatory emails you receive and facts and figures, i.e. the report showing sales grew 50% under your helm. Keep them in an email folder, a physical folder or a journal but just keep track, recommends Goodwin.

"I'm a huge fan of a work journal where you write down each day or each week what you learned, what you got done, any compliments you received," she said. "It really helps you look back at what you’ve done and what you’ve accomplished -- a paper trail."

In addition to tracking your accomplishments yourself year-round, make sure your boss is aware too.

"Ideally you should be coming up with goals with your boss -- goals and key performance indicators -- because you want to make sure that what you’re working on matters to them," said McGoodwin. "Once a month or every two months or every six weeks, have a check-in about where you stand with your goals."

"Then after every meeting send a recap email so they have a written copy of what you've achieved," she said.

There's also a side bonus: you will get used to talking with your boss about your wins so the year-end meeting is not as awkward.

2. Go in with a goal:

Think ahead of time about what you want to get out of the meeting with your boss, whether it's a raise, a promotion or something else, advises McGoodwin.

If you're asking for a raise or promotion, she notes, think ahead about a script to tell your boss why you have earned one. The "earned" part is important because it's key to talk about how you earned it, not why you deserve it, according to McGoodwin.

A script for the conversation with your boss should include things like the assets you bring to the team, new skills you've gained over the past year and your accomplishments. It should also look ahead to the future, noting how you plan to contribute and grow.

"The more you talk about your accomplishments, talk about what you want, what you’ve done well and the value you’ve brought, you're writing your own story line," said McGoodwin, who also recommends videotaping yourself as a way to prepare for the meeting.

3. Make this one thing all about you:

Use only "I" not "we" when writing a performance review, advises McGoodwin.

"Using we doesn't send a confident message," she said. "Be aware of the language you’re using so it’s very assertive."

For women who may be uncomfortable with writing something all about themselves, McGoodwin has this advice: "Don’t think about yourself reading it but the person on the other end."

4. Talk accomplishments, not responsibilities:

"I say, 'Don’t tell me your responsibilities, tell me your accomplishments,' and women look at me like I’m talking a different language," said McGoodwin. "Women are definitely rule-followers but you can be more creative when it comes to thinking about your job and your career."

If, for example, your job responsibility is to post on Instagram, instead tout an accomplishment like, "Engagement on Instagram has increased by 50%."

If your job responsibility is to answer the phone, a response could be, "Answer and manage an average 50 phone calls per day."

5. Schedule a post-review debrief with yourself:

"After you have conversations that make you uncomfortable or are intimidating, schedule a debrief with yourself on what went well and what you’d like to change in the future," said McGoodwin. "A woman's inner critic will often come out of the woodwork so use the debrief to reframe it."

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