Astrid was happy to get some credit for her answer. She knew that she had messed up the wording somehow. She raised her hand again, hoping to do a little better with this answer.

"Your four Challenge Numbers go right along with your Pinnacle Numbers and cover the same years. They are found in your date of birth just like the Pinnacles, but instead of adding the numbers in your date of birth, the Challenges are found by subtracting them."