Item4 10 points my workCheck My Work button is now enabledItem 4 Using the following data on bond yields: This Year Last Year Yield on top-rated corporate bonds 5.9 % 8.9 % Yield on intermediate-grade corporate bonds 7.9 % 10.9 % a. Calculate the confidence index this year and last year. (Round your answers to 4 decimal places.) b. Is the confidence index increasing or decreasing? multiple choice Increasing Decreasing