Freedom of Information request - Car Usage in London: Update
Request ID: FOI-1330-2324 Date published: 21 August 2023
You asked
Follow-up to TfL Ref: 0532-2324. As per my correspondence dated the 19th June, the Principal Analyst is clearly incorrect as regards their estimation of costs. Your correspondence states that 162 separate searches must be run in order to generate the data - presumably searches for each of 3 years x 3 areas x 3 days of the week. Although they cite that these data are stored in heirarchical databases, a single query could be constructed for each question for of the years requested, which would presumably follow an identical schema given the near-identical structure of the underlying database. Given that I have provided the overarching query structure which would reduce this request to 12 searches across 3 separate years, it is somewhat worrying the Principal Analyst still states that these will require separate manual searches, as it would indicate an inefficiency of analysis which would if true be hampering TfL's ability to use the data it owns to correctly set and update policy.
The panel states they expect that generating the data originally requested would take 27 hours of staff time under a conservative estimate. While this is plainly incorrect, the FOI Act requires a public body to assist the requester in requesting a subset of data which would be allowed within cost limits.
As such, I would like to revise my request as follows, which would reduce your claimed 27 hours of staff time to between 2 and 6 hours of staff time, by requesting only the data for the latest available year (a 66% reduction), and by asking for a split between weekdays and weekend days, rather than splitting weekdays from Saturday from Sunday (a 33% reduction). Furthermore, I will rescind my request for the final set of data, by-hour car trip data, in case in the opinion of the Principal Analyst this is driving a disproportionate amount of the manual queries they believe they would need to run. My expectation is that this will have reduced the amount of work the team believe would be required by at least 93%, which would imply a time to deliver of 2 hours. Presuming your initial estimates of time to deliver were correct, this would plainly sit within the 18 hours prescribed under FOIA.
My revised freedom of information request is as follows:
Could you please provide the following data based on the London Travel Demand Survey for the latest year’s survey:
- the average daily trip rates and travel distances for each travel mode, splitting week days from weekend days (the current LTDS worksheet aggregates travel distance between weekend and week day)
- for car drivers and car passengers, the average daily trip rates and travel distances for each purpose listed in Technical Note 14 (Work, Education, Leisure, Shopping/Personal, Other)
- finally, for car drivers and car passengers, the proportion of weekday and weekend travel, by purpose, split by the distance of trip as in Figure 3 of Technical Note 14 (<1k, 1-2k, 2-3k, 3-4k, 4-5k, 5k+)
For each data point requested could you show data for Greater London as a whole, Inner London, Outer London and Trips Wholly Within Greater London as within the London Travel Demand Survey workbook (https://content.tfl.gov.uk/ltds-0520.xlsx)
We answered
TfL Ref: 1330-2324
Thank you for your request received by Transport for London (TfL) on 26 July 2023 asking for information about data based on the latest London Travel Demand Survey.
Your request has been considered in accordance with the requirements of the Freedom of Information Act and our information access policy. I can confirm that we hold the information you require. You asked: for
data based on the London Travel Demand Survey for the latest year’s survey:
- the average daily trip rates and travel distances for each travel mode, splitting week days from weekend days (the current LTDS worksheet aggregates travel distance between weekend and week day)
- for car drivers and car passengers, the average daily trip rates and travel distances for each purpose listed in Technical Note 14 (Work, Education, Leisure, Shopping/Personal, Other)
- finally, for car drivers and car passengers, the proportion of weekday and weekend travel, by purpose, split by the distance of trip as in Figure 3 of Technical Note 14 (<1k, 1-2k, 2-3k, 3-4k, 4-5k, 5k+)
For each datapoint requested, could you show data for Greater London as a whole; Inner London, Outer London and Trips Wholly Within Greater London as within the London Travel Demand Survey workbook (https://content.tfl.gov.uk/ltds-0520.xlsx)
Please see the attached spreadsheet for the requested data based on the most recent London Travel Demand Survey, covering the financial year of 2022/23.
If this is not the information you are looking for, or if you are unable to access it for any reason, please do not hesitate to contact me.
Please see the attached information sheet for details of your right to appeal as well as information on copyright and what to do if you would like to re-use any of the information we have disclosed.
Yours sincerely
Jasmine Howard FOI Case Officer FOI Case Management Team General Counsel Transport for London
