(CBS Local) — You probably already suspected it, but now it’s confirmed. Fast food drive-thru lines are slowing down in the United States, according to a new report.

Customers spent an average of 255 seconds this year going from the speaker to place their order to the pick up window, according to a performance study from restaurant trade publication QSR Magazine.

That’s about 20 seconds longer than in 2018.

The study found Dunkin’ had the fastest drive-thru times, with an average of just over 216 seconds. Wendy’s and Burger King followed as the second and third-fastest, respectively.

Chick-fil-A finished last, with an average time of over 322 seconds, “due to its constantly crowded lanes,” the study found.

QSR notes that Chick-fil-A has attempted several strategies to help speed up their drive-thrus, such as stationing employees with iPads outside to take orders and payments.

Other chains are also experimenting with new technologies to help speed up the takeout process. Multiple restaurants offer ordering via smartphone app, allowing users to place their orders in advance, then pick them up at the desired location.

But with increased orders and more complex menus, it’s going to be difficult for brands to shave off seconds moving forward, the magazine predicts.

According to QSR’s study, here are the average speeds of service by seconds:

Dunkin’: 216.75 seconds
Wendy’s: 230.38
Burger King: 235.48
Taco Bell: 240.38
Carl’s Jr.: 240.51
KFC: 243.73
Arby’s: 263.46
Hardee’s: 266.34
McDonald’s: 283.05
Chick-fil-A: 322.98

The study involved more than 1,500 visits to the fast food chains. Visits were conducted across the country, and at different times during the day between June 1 and Aug. 1, according to QSR.