* No Centralized Record: In Dickens' time, there wasn't a system for tracking book sales across all publishers and retailers.
* Different Formats: Dickens' works were published in various formats, including serialized installments in magazines, individual volumes, and collected editions.
* Time Period: Dickens wrote and published throughout a significant portion of the 19th century. His sales numbers fluctuated over time.
However, we can say that Dickens was incredibly popular in his time. His works sold in massive numbers, and he was one of the best-selling authors of his era. His novels were widely read by all levels of society, and he was a household name.
If you'd like to learn more about the popularity of specific Dickens titles or his publishing strategies, I can help you find information from literary sources or historical data.