Transport

(asked on 2nd July 2019) - View Source

Question to the Department for Transport:

To ask the Secretary of State for Transport, pursuant to the Answer of 24 June to Question 266291 on Transport: Exhaust Emissions, what methodology his Department used to provide real term changes in percentages in cost of transport in the Answer of 16 January 2018 to Question 121761 on Travel.


Answered by
Michael Ellis Portrait
Michael Ellis
This question was answered on 8th July 2019

Rail, Bus and Coach and Motoring

The real terms changes in percentage costs for years 1997, 2010 and 2015 were calculated using the components of Retail Price Index (RPI) from the ‘RPI All Items Index 1987=100’ available from the Office for National Statistics:

https://www.ons.gov.uk/economy/inflationandpriceindices/timeseries/chaw/mm23

These figures are based on the following component categories:

CHAW- RPI All Items; DOCW-Rail Fares; DOCX- Bus and Coach Fares; CHBK- Motoring

These component categories have been annualised and re-based to 1997, 2010 and 2015 for comparison to 2016. The RPI All Items index was used to calculate the real terms increases for each transport component.

Transport cost increases from 1980 use historic ONS RPI data. This is due to RPI being re-based in 1987. Pre-1987 codes for transport components were matched to the new categories using the code descriptors, which had remained unchanged. The historic data is not published online. The real terms increase from 1980 was then calculated using the same methodology as above.

While information prior to 1987 was provided in previous PQ responses, it was drawn from historical data which is not readily available and will no longer be provided in future.

Aviation

The costs of travelling domestically by air are based on fare data taken from the Civil Aviation Authority passenger survey. The Retail Price Index (RPI), taken from the Office for National Statistics, has been used to adjust for the real term change in the costs. As no separate RPI index is available for domestic air fares, the overall index for transport components has been used.

This index is available from Table TSGB1308 in the Transport Statistics Great Britain Compendium at the link below:

https://www.gov.uk/government/statistical-data-sets/transport-expenditure-tsgb13

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