The processed bike share ridership data consists of the following files

1. 2018, 2019
   1. eight quarterly CSV files
2. 2020, 2021, 2022
   1. 36 monthly CSV files
3. 2023
   1. 12 monthly CSV files

Raw bike share ridership data contains the following columns per trip

1. Trip Id
   1. bike share trip identifier
   2. this is a nominal value
   3. in data from 2018, this is trip_id
2. Trip Duration
   1. trip length in seconds
   2. in data from 2018, this is trip_duration_seconds
3. Start Station Id
   1. identifier for station from which bike was checked out to start trip
   2. in data from 2018, this is from_station_id
4. Start Time
   1. date and time at which trip started
   2. in data from 2018, this is trip_start_time
5. Start Station Name
   1. name of station from which bike was checked out to start trip
   2. in data from 2018, this is from_station_name
6. End Station Id
   1. identifier of station at which bike was returned at end of trip
   2. in data from 2018, this is to_station_id
7. End Time
   1. date and time at which trip ended
   2. in data from 2018, this is trip_stop_time
8. End Station Name
   1. name of station from which bike was returned at end of trip
   2. in data from 2018, this is to_station_name
9. Bike Id
   1. identifier for bike used in bike share trip
   2. in data from 2018, this is column is missing
10. User Type
    1. type of bike share member
    2. one of Annual Member or Casual Member
    3. in data from 2018, this is user_type