I was amazed at what I learned in this book. I have been using Excel Power Query for a year and I had missed so many features. After reading the first 7 chapters of this book, I was doing a seminar for a client. They had a horrible-looking file being produced by Oracle. It took an intern almost a whole day to clean the file so it was usable. In less than 10 minutes with Power Query and my new-found tools, we had cleaned the entire file. The monthly process will now take 2 clicks instead of eight hours. If there was ever a book that would revolutionize white-collar productivity with Excel, this is the book.