the Los Angeles Times has found a way to quantify the driving experience on LA freeways using data from Caltrans.

The LA Times ranked 25 freeways from best to worst, with the toll road State Route 261 taking top honors and the 10 Freeway ranking as the worst.

The factors used were the average speed of every car to use the freeway over a one-year period, 

• the hours lost to delays on that road, 
• the lost productivity caused by those delays
• and a metric for number of fatalities on the road in a given year,
• all scaled by how many cars use the road and how long the road is

In fact, the numbers show the 10 Freeway is the worst, which scored an astounding -1,300 on a scale intended to range from -500 to 500, with 0 being about average.

from best to worst: 

• State Route 261 
• State Route 90 
• State Route 241 
• State Route 126 
• I-15 Freeway 
• State Route 73 
• State Route 118 
• State Route 71 
• State Route 170 
• I-5 Freeway 
• State Route 134 
• State Route 22 
• I-105 Freeway 
• I-210 Freeway 
• I-215 Freeway 
• U.S. 101 Freeway
• State Route 55 
• State Route 60 
• State Route 57 
• I-110 Freeway 
• I-710 Freeway 
• State Route 91 
• I-405 Freeway 
• I-605 Freeway 
• I-10 Freeway

That performance led the Times to call driving on the 10 “46.8 nightmarish miles from the ocean through the city.”

The next closest score was the 605 Freeway, a “notoriously jammed road” that scored -600.

 The 405 — “72.8 miles of frustration” — was next at -500.

https://ktla.com/news/local-news/the-405-isnt-the-worst-freeway-in-southern-california-analysis-finds/

https://www.cbsnews.com/losangeles/news/southern-california-best-worst-freeways-ranked