“We select such investments on a long-term basis, weighing the same factors as would be involved in the purchase of 100% of an operating business:
(1) favorable long-term economic characteristics;
(2) competent and honest management;
(3) purchase price attractive when measured against the yardstick of value to a private owner; and
(4) an industry with which we are familiar and whose long-term business characteristics we feel competent to judge.”