Dear Kathleen Desveaud

I think it is better to limit this data to a specific country because difficult if the data global It is to have an accurate figure, especially since you covered marketing in general and not one of the marketing axes, for example digital marketing, tourism marketing or green marketing.

in this link you can see main stage of marketing maybe help you take one stage of them to be more accurate

https://blog.oxfordcollegeofmarketing.com/2012/11/23/the-6-main-stages-in-marketings-history/

Dear Kathleen,

Please check the following link for marketing research in 80s and 90s:

https://link.springer.com/chapter/10.1007/978-3-319-16973-6_35

Kindly refer,

Hair, J. F., Celsi, M., Ortinau, D. J., & Bush, R. P. (2008). Essentials of marketing research. New York, NY: McGraw-Hill/Higher Education.

Krasnikov, A., & Jayachandran, S. (2008). The relative impact of marketing, research-and-development, and operations capabilities on firm performance. Journal of marketing, 72(4), 1-11.

Parasuraman, A., Grewal, D., & Krishnan, R. (2006). Marketing research. Cengage Learning.

McDaniel, C., & Gates, R. (2013). Marketing research. Singapore.

Thank you very much, I'll have a look at the references you sent me :)

Hi Timo,

Thank you very much ! Very interesting reference matching well what I was looking for :)

Best,

Kathleen

I Agree With Mahmoud Alghizzawi