In 2012, Rob met Susan at a party. Susan told Bob she was directing a business venture that bought poorly managed restaurants in order to turn them around, and she found a real "gold mine" but needed additional cash in order to purchase it. Bob loaned $100,000 to Susan under a written agreement whereby Susan would repay the loan for a five year period plus 15 percent interest annually on the unpaid balance. Later in the year, Bob discovered Susan never intended to purchase the restaurant and had used the money for her personal benefit. He then sued Susan in 2014, but was unable to recover any of the $100,000. Discuss the tax treatment that Bob may take with regard to this loan.