Consider a secretary's performance, which might be measured by number of breaks per hour and the time required to complete reports. The two measures are orthogonal because they do not overlap. However, it is possible that repeated evaluations could show a reliable association between a higher number of breaks per hour and less time required to complete reports. The history of General Electric provides a clear example of developing orthogonal performance measures. When GE dismantled its conglomerate in the 1950s, its existing performance measures, which relied on centralized budgetary targets, needed to evolve to suit the newly decentralized company. The 1951 GE Measurement Project provided a template for the new performance measures, which were orthogonal to the old performance measures, as well as to each other. The new measures were "profitability, market position, productivity, product leadership, personnel development, employee attitudes, public responsibility", and balance between short-term and long-term goals. Thirty years later, when the company was in dire straits, the performance measurements were functionally consolidated into ranked profitability and growth. With this strategy, GE annually swept away the bottom 10% of its performers in profitability and growth. Once GE regained financial and market stability, the performance evaluation metrics changed in response, allegedly expanding and taking on more humanistic values. GE illustrates two important notes about changing performance metrics. First, new performance measures are most useful when they are unrelated to each other and to existing measures. Second, performance measures tend towards elaboration during times of security and profitability, and likewise tend towards consolidation during times of urgency and strain. Orthogonality has been shown in the history of many industries, particularly to reflect changing expectations. American hospitals used to measure success by patient outcome. In the early 1900s, however, a study showed such dismal results with patient outcomes that the study and its results were burned, and hospitals instead evaluated performance by the keeping of records and adherence to procedures. With time, societal expectations of low patient mortality have led to hospitals reinstating the patient outcomes as a measure of success. Evolving technology have also forced the development of orthogonal measures. As early as 855, the success of texts was measured by print runs. In 1942, The New York Times began publishing a list of best-selling books, which has been shown to influence the purchases of the majority of American book buyers. The NYT Bestseller list is divided into section, including fiction, non-fiction, and children's literature. With the advent of e-book technology, the NYT added an orthogonal e-book section to the list.