Read the following table carefully and answer the following questions:

Production of five brands of cars in 5 years from 2001 to 2005

Years	Brand Name
	P	Q	R	S	T
2001	75	60	75	55	65
2002	85	50	60	90	85
2003	80	85	65	45	55
2004	65	90	70	80	75
2005	45	55	90	70	90

Find the average production of cars of brand R in five years?