Problem: The U.S. Trade Deficits for the first half of 1989 are shown on the next page in Figure 6.9. Plot these values and their moving ranges on the form given in Figure 6.10.

Understanding Variation / Managing Chaos Jan Feb Mar Apr May Jun 1989 8.7 8.7 7.0 6.8 9.6 9.0 Figure 6.9: Monthly U.S. Trade Deficits, 1989 ($ billions) Jan Feb Mar Apr May Jun X MR 13.0 12.0 11.0 Trade Deficits ( X ) 10.0 9.0 8.0 7.0 6.0 3.0 2.0 Moving Ranges 1.0 0 Figure 6.10: Form for Xml Chart There are two indications of shifts in Figure 6.10. The first shift was favorable, and the second was unfavorable. 9. When is this favorable shift detected? 10. When might this favorable shift have begun? 11. When is the unfavorable shift detected? 116