(CNN) -- Are they nervous, or bored, or completely oblivious? There's no one-size-fits-all diagnosis for the airplane seat kicker, but they're universally annoying.
For the third year in a row, rear seat kickers have earned the dubious distinction of being the No. 1 most offensive type of airline passenger.
They beat out inattentive parents, aromatic passengers, seat recliners and more in the fourth annual Expedia Airplane Etiquette Study, released Tuesday.
Drawn from feedback from 1,005 Americans age 18 and over, the study shows that 64% of respondents find the rear seat kicker annoying. Inattentive parents rank second, aggravating 59% of those surveyed, followed by smelly or "aromatic" passengers (55%).
Rear seat kickers have topped the rankings since 2014. In 2013, the first year of the study, inattentive parents topped the list.
Despite some variations, there's a common theme from study to study.
"A prevailing theme across all four years of the study is the importance people place on the sanctity of their personal space within the tight confines of an airplane," said Dave McNamee, Expedia spokesman.
The good news?
"A sizable majority of Americans -- 70-80% of people -- consider their fellow passengers to be 'considerate,'" McNamee noted.
Annoying passenger rankings
So how do all the aggravating passengers stack up? Here's the full 2016 list:
1. The Rear Seat Kicker (cited by 64% of respondents)
2. Inattentive Parents (59%)
3. The Aromatic Passenger (55%)
4. The Audio Insensitive (49%)
5. The Boozer (49%)
6. Chatty Cathy (40%)
7. The Queue Jumper (35%)
8. Seat-Back Guy (35%)
9. The Armrest Hog (34%)
10. Pungent Foodies (30%)
11. The Undresser (28%)
12. The Amorous (28%)
13. The Mad Bladder (22%)
14. The Single and Ready to Mingle (18%)
Commissioned by online travel company Expedia, the study was conducted by GfK, an independent market research company.
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