You asked
I am interested in the relationship between market structure and advertising content in the UK automotive and airline industry.
To be able to relate these two variables, I am looking for data that will help me to determine a parameter for the intensity of competition (such as the four-firm concentration ratio or the Herfindahl Hirschmann Index (HHI)) between 1930 and 2014. Do you maybe know of a database or by any chance have data on which automobile companies or airlines were the market leaders during the years of the twentieth century and what their market share was in the UK?
Alternatively, do you have data on, for example, the number of new car registrations sorted by brand for these years?
We said
Thank you for your request.
Unfortunately we do not hold the information you have requested. The Department for Transport (DfT) and the Department for Business, Energy, and Industrial Strategy (BEIS) may be better placed to answer your request. They can be contacted via the following links respectively: Department for Transport Contact Form and foi.requests@beis.gov.uk.