Q: Passage: Google Traffic works by analyzing the GPS-determined locations transmitted to Google by a large number of mobile phone users. By calculating the speed of users along a length of road, Google is able to generate a live traffic map. Google processes the incoming raw data about mobile phone device locations, and then excludes anomalies such as a postal vehicle that makes frequent stops. When a threshold of users in a particular area is noted, the overlay along roads and highways on the Google map changes color.

Question: Based on this passage, where does google maps get its traffic data from?
Let's give stream of consciousness below

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
The important part for answering this question is: Google Traffic works by analyzing the GPS-determined locations transmitted to Google by a large number of mobile phone users. So the answer is analyzing the GPS - determined locations transmitted to Google by a large number of mobile phone users.