Suppose that the 1-year spot rate, 2-year spot rate, 3-year spot rate, and 5-year spot rate are 4.3%, 4.7%, 5.1% and 5.9%, respectively, and these are quoted as annual effective rates. Determine the 4-year spot rate (effective annually) if the swap rate for a 5-year swap is 5.8%. (Reminder: Please express your answer as a decimal, not percentage. For example, if your answer is 8.15%, please write 0.0815 instead of 8.15% or 8.15.)