An account owner makes an initial deposit on 1 January of $10,000.

(i) At the end of the first year, the account value is $12,000, and she then makes a withdrawal of $2,000. (ii) At the end of the second year, the account value is $8,500, and she makes a deposit of $2,000.

(iii) At the end of the third year, the account value is $12,000. What is the dollar-weighted three-year rate of return on this account?