Terry purchased stock in Yippee Corporation for $10,000 in May 1977. He bought stock in Zapper Corporation for $20,000 in June 1980. The Yippee Corporation stock is currently worth $90,000, and the Zapper Corporation stock is worth $15,000. Terry is in very poor health, and he comes to you for tax advice. What advice would you give him regarding his stock holdings? Is there any additional information you would like to ask him for before giving him tax advice?