Hong runs a large animal shelter. The Amador family adopted a puppy named Birdie from the shelter. When Birdie was adopted, she had been at the shelter for 25 days. At Hong's shelter, the length of stay for puppies has a mean of 43 days and a standard deviation of 13 days. Find the z-score of Birdie's length of stay at the shelter relative to the the lengths of stay for all the puppies at the shelter. Round your answer to two decimal places.