What is historical or economic issue does the author(s) address with their new data?

reading the file and answer the following question. PLEASE write more on question 3
1. What is historical or economic issue does the author(s) address with their new data?
2. What are the data and what are the sources?
3. Are there any concerns about the data noted by the author?
4. What methods does the author use to analyze the data?
5. What do we learn about European economic history from the new data?