Use the following sales data to compute a trend and seasonal
Use the following sales data to compute a trend- and seasonally-adjusted forecast for quarter 3 of year 7. Round off seasonal indexes to two decimals.
18) Use the following sales data to compute a trend- and seasonally-adjusted forecast for quarter 3 of vear 7. Round off seasonal indexes to two decimals. Year Quarter 2008 86.4 93 91.9 107.3 2009 95.3 102.7 98.6 107.9 2010 93.5 100.9 99.4 113.7 2011 99.1 103 101.2 115.6 2012 103.4 108.6 109.5 122.3 2013 113.4 113.5 113.2 127.1 A. 109.4 B. 125.8 C. 114.6 D. 115.7Solution
Hence for quarter 2007 iii quarter x = -1
Substitute in the regression equation
y = 90.946-1.126
= 89.82
