A $40,000 investment yields payments of $20,000, $22,000, $23,000, $20,000, and $25,000 at the end of years 1, 2, 3, 5, and 6 respectively, Calculate the rate of return (ROI) represented by this cash flow to three significant figures. If you were offered an additional $20,000 at the end of any of the years and you could choose the year, which would be the best year and what would be the new ROI? Aside from ROI considerations, is there another factor to be considered, and when would you add the $20,000 based on this consideration.