The fo llo w in g table shows a p o rtio n o f the percent change in the consum er price index (CPI) fo r the United States from 1980 through 2008; the full data set can be found on the text website, labeled US CPI. Use the m ethod o f runs above and below the m edian w ith a significance level of 5% to test the null hypothesis of random ness against th e alternative th a t there is a tren d or cyclical pattern.

Year CPI 1980 12.5 1981 8.9

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2008 0.1