$15.00 books netted a $17,000 annual raise

Just wanted to share the following story:

A friend just sent a copy of my book to her nephew in Washington State. What he got from the book is that there are good jobs with current employers. He was ready to leave his company and after reading the book he applied for a management position that he did not believe he could get and got a $17,000 raise. What a return on investment? $15.00 books netted a $17,000 annual raise.