If the index was at 62.8 in April 2008, what does that mean for May ...

  

(a) A base is first selected. In this case, the base was 1985 and set at 100. Thus, if the index is at 57.2 in May 2008, and October 1992 was at 54.6, are people feeling better or worse than they did in 1992?

(b) If the index was at 62.8 in April 2008, what does that mean for May? 

(c) Why do we use indexes?