SAN FRANCISCO (KCBS) – Think you’ve been getting up early enough to avoid traffic? New data from the Metropolitan Transportation Commission obtained by KCBS suggests you may have to set the alarm even earlier.

Numbers from the MTC show traffic in the 4 a.m. hour is up 36 percent at the Bay Bridge from 2014-15 to 2016-17. Early traffic at the Richmond-San Rafael Bridge is up 20 percent, while the San Mateo Bridge is up 31 percent.

“It is pretty darn early,” said John Goodwin of the MTC.

The latest numbers show 33,000 more vehicles at the Bay Bridge toll plaza in the 4 a.m. hour in June of this year compared to two years ago. In the 5 a.m. hour, it was only a 7,000 vehicle increase.

“There is still a big difference between traffic in the the 4 o’clock hour and traffic in the 5 o’clock hour,” Goodwin told KCBS. “But what we do see is a strong and steady increase in the 4 o’clock hour.”

Who is coming in this early? Construction crews, early office janitorial workers or penny pinchers looking to avoid the rush hour toll hike.

On weekdays, tolls at the Bay Bridge increase from $4 to $6 at 5 a.m.

“Is it at 4 a.m., is it at 4:30 or is it at 4:50? If it’s at 4:50? There’s probably people trying to beat the toll,” said Jason Henderson, who studies transportation and land use at San Francisco State University.

Henderson blames the early wake up calls on the housing crunch.

“You work in servicing a Google, Facebook or a Twitter or some Financial District building, and it needs to be cleaned before 8 a.m. You can’t easily change your housing, so people get locked into these long, arduous commutes,” Henderson said.

The earlier commutes could prompt transportation planners to consider things like 24/7 carpool lanes and tolls, just like they have in Los Angeles.

“Little by little, the difference between traffic conditions in the Bay Area and traffic conditions in Southern California is shrinking. We are becoming more like our neighbors to the south,” Goodwin said.