You have estimated the payout of your company's December 31, 1991 accident year 1991 auto liability loss reserve to be as follows Calendar year 1992 1993 1994 1995 1996 % of 12/31/1991 loss reserve paid in year 30% 25% 20% 15%|10% Assuming all future payments are made at midyear, and an expected future investment yield of 8%, what average Macaulay duration of assets do you need in order to duration match your auto liability portfolio