using W=0.25 Decade Performance(%) 1830 2.6 1840 12.2 1850 5.6 1860 11.3 1870 7.4 1880 5.9 1890 5.4 1900 10.8 1910 1.9 1920 13 1930 -2.7 1940 9.6 1950 18 1960 7.9 1970 6.4 1980 16.9 1990 17.4 2000 -0.7 What is the exponentially smoothed forecast for the 2010 s? %.