That’s a big bounce, from 27 percent two years ago to 43 percent this time around. A Fidelity spokesman says that could be because more workers are now freelancing or working multiple jobs with unpredictable hours and others take bonuses as a big part of annual income - an amount hard to guess ahead of time.

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According to the survey, Generation X, in their late 30s and 40s and at the peak of their careers, is also the worst at guessing a partner’s income. The Fidelity spokesman says, again, bonuses may be throwing the guess off.

Baby boomers approaching retirement were wrong 42 percent of the time, while the younger working adults - millennial - were wrong only 34 percent of the time.