The amount of rainfall over a five-day period in Savannah, Georgia is 2.1 inches, 2.3 inches, 1.6 inches, 1.2 inches, and 1.8 inches. Last year, the five-day average rainfall for these same dates was 2.1 inches.

On average, how much less rain did Savannah receive this year than last year for these dates? Write your answer as a decimal.