TITLE
"A Comparison of Large Firm Dominance in Property and Liability Insurance with Major Industries," Journal of Insurance Issues, Edward Nissan and Regina Caveny, Spring/Fall 2001, Vol. 24, No. 1&2, pp. 58-73. Entire article in Acrobat format.

ABSTRACT
This article compares the concentration of property and liability insurance by line with a host of other industries. Measurements used are the Herfindahl and the concentration ratio.  It was found that four of the lines distinguish themselves as the most concentrated among the top property and liability insurance lines, far exceeding the concentration of all others.