To answer this question, we should know that: The Cadillac SRX is a mid-size luxury crossover SUV that was produced by Cadillac from 2004 to 2015.is the reasoning for what question and answer pair?
Q: The Cadillac SRX is a mid-size luxury crossover SUV that was produced by Cadillac from 2004 to 2015. The second generation SRX was Cadillac's best selling model in the United States.

Based on this passage, what year did the cadillac srx come out?
A: 2004