Maria from NY asked TeamTCL the question in the title.
🗒️
Maria, who describes herself as an experienced industry professional, is involved in writing a research paper.
Maria, I am sorry to say that I was unable to find any publicly available research that answers this question. I was able to find some research going back as far as about 2003, but nothing older than that.
If you’re a ChocolateLife member and have access to research that might help Maria out, we’d all appreciate your posting an answer and your source(s) in the comments. You must be a member to comment, but you can join for free if you are not a member.