At the beginning of the year, William bought 20 shares of Zync Corporation at $18.50 per share. Zync pays dividend at the end of each year based on annual profits, which generally vary substantially from year to year. In its 25 years history, Zync has paid dividends every year without fail. The initial investment by William and the receipt of dividend at the end of every year are examples of a(n) and a(n) , respectively.