Suppose Indonesia produces only milk and butter, and the Statistics of Indonesia has published the following macroeconomic data, where quantities are in gallons and prices are dollars per gallon.

	2015	2016
	Quantity	Price ($)	Quantity	Price ($)
Milk	900	3	500	2
Butter	3000	2	2000	1

Using GDP deflators in 2015 and 2016, please calculate how much the GDP deflator change (consider Year 2015 as the base year) between Year 2015 and Year 2016. Percent change in GDP deflator from 2015 to 2016 is