I want to know the answer to the following question:
In what year did IBM add sexual orientation to their nondiscrimination policy?
All the background I'm provided with is that "He also publicized the policy so that in his negotiations to build new manufacturing plants with the governors of two states in the U.S. South, he could be clear that IBM would not build "separate-but-equal" workplaces.". Is that enough to answer the question?