Australia's Suncorp falls on $228 million net cost from thunderstorm

** Shares of Suncorp Group SUN drop as much as 3.3% to A$17.950, their lowest since April 8

** Insurer says net cost from supercell thunderstorms in Queensland and northern New South Wales is expected to be about A$350 million ($228.38 million), hitting its reinsurance retention limit

** Co has received over 10,000 claims so far, split evenly between home and motor, following large hail and destructive winds

** Stock down 3.8% YTD, including the day's moves