An investor bought $70$ shares of stock at a cost of $$$$11$ per share. He held the stock for $14$ years and then sold it for a total of$$ $$3080$ For the first two $$years$,$ he received no dividends. For each of the next six $$years$,$ he received total dividends of $$60$ per year. For the remaining$$ period, he received total dividends of $$$$120$ per year. What rate of return did he make on the$$ investment?