Kemper down after William Blair downgrades stock to 'underperform'

Shares of U.S. insurance provider Kemper Corp KMPR.N fall 3% to $39.92 premarket

William Blair downgrades stock to "underperform" from "marketperform"

Brokerage says co faces dual threat of overexposure to a worsening California market and big competitors coming down into the non-standard segment

Says KMPR to face greater downside risk if it continues to face significant adverse development in its commercial auto business

Three of 6 brokerages rate stock "buy" or higher, 2 "hold" and 1 "sell" or lower; median PT is $110 - data compiled by LSEG

As of last close, stock down 38% YTD