2014 2015 Real GDP growth (annual percent) 3.6 3.9 Inflation (annual percent) 5.2 5.6 Interest rate (nominal, annual percent) 6.3 6.9 Government deficit (primary, percent of GDP) 3.9 1.7 Government deficit (total, percent of GDP) 5.1 5.2 Government debt (end of period, percent of GDP) 35.0 ? What is the difference between real interest rates in 2015 and 2014? A. -0.5% B. 0% C. 2.4% D. 0.2%