Your financial planner offers you two different investment plans. Plan X is a $10,000 annual perpetuity. Plan Y is a 18-year, $18,000 annual annuity. Both plans will make their first payment one year from today. At what discount rate would you be indifferent between these two plans? (Do not round intermediate calculations. Enter your answer as a percent rounded to 2 decimal places, e.g., 32.16.)