Shown below are the top 15 market research firms in the United States in 2010 according to Inside Research and the 2011 Honomichl report. Compute the mean, median, P30, P60, P90, Q1, Q3, range, and the interquartile range on these data.
Company ............. Sales ($ millions)
The Nielsen Co. ......... $2,407.0
Kantar .............. 914.7
IMS Health Inc. ......... 801.0
Symphony IRI Group. ....... 457.0
Westat Inc. . ........... 455.3
Arbitron Inc. . ......... 390.4
Ipsos. ............. 379.6
GfK USA. ............ 290.9
Synovate. ........... 235.8
The NPD Group Inc . . . . ....... 173.7
ICF International Inc . . . . ....... 153.2
J.D. Power and Associates. ...... 147.3
comScore Inc. . ......... 142.0
Maritz Research. ......... 140.9
Dunnhum by USA LLC. ....... 110.7