You will be given a definition of a task first, then some input of the task.
In this task, you will be presented with a question and you have to answer the question based on your knowledge. Your answers should be as short as possible.

What is an estimate ridership of this public transportation agency that operated bus and historic streetcar service in a city that was heavily affected by a hurricane on August 29 , 2005 ?
Output:
18.6 million riders