please answer part A

Using the following data on bond yields: Yield on top-rated corporate bonds Yield on intermediate-grade corporate bonds This Year 5.2% 7.2% Last Year 8.2% 10.2% a. Calculate the confidence index this year and last year. (Round your answers to 4 decimal places.) Answer is not complete. Confidence Index This year Last year b. Is the confidence index increasing or decreasing? Increasing Decreasing