Do you know how much money your spouse or partner makes?
According to the 2015 Fidelity Investments Couples Retirement Study, about four in 10 couples cannot answer this question correctly, and one in 10 of those couples were off in their estimates by $25,000 or more.
Both men and women were equally clueless — and wrong 43 percent of the time.
Additionally, 36 percent of couples in the survey disagreed on the amount of their household's total investible assets.
Baby Boomer couples did the best, followed by millennial couples, with Gen X couples bringing up the rear.
Related Link: The 3 Biggest Money Mistakes Couples Make
Nearly half of the surveyed couples (47 percent) disagreed on just how much they need to save in order to maintain their lifestyle in retirement, with 48 percent of the couples saying they had "no idea."
More than half (52 percent) did not know how much they could expect to receive in retirement income each month.
When it came to Social Security, 60 percent of couples did not know or weren't sure how much their benefits might be worth. Almost half (49 percent) of Baby Boomers fell into this category. This news is surprising, given that many Baby Boomers are on the brink of retiring or in retirement already.
Not knowing your actual household income can make it difficult to plan for the future, especially when it comes to saving and planning for retirement. It also can have major consequences if there is a divorce.
Related Link: Why Money Arguments Are a Red Flag for Couples
The last time Fidelity conducted this study in 2013, 27 percent of couples couldn't accurately state their partner's income. The big jump in that figure this year may be related to the increasing popularity of project-based work, with 40 percent of workers now employed on a freelance or contingent basis. With more income fluctuations from year to year, annual incomes may be harder to know and predict.
The Fidelity study looked at 1,051 couples who were either married or living together in long-term relationships, with a minimum household income of $75,000 or at least $100,000 in investable assets. Participants were at least 25 years old. The study included 596 retired and pre-retired couples (age 47 or older), 154 Gen X couples (ages 35 to 46,) and 301 Gen Y couples (ages 25 to 34).
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