OUTSURANCE DOUBLING MY PREMIUM?!!

Ive had 4 policies with Outsurance for the past year. Each policy has 2 to 15 items on the policy. From cars, residental homes, business offices and farm implements. Ive had minimal claims on 3 of those policies - the claims do not even come to 10% of the total premiums I have been paying. This week I get rerate emails from Outsurance - the one policy's premium is doubling and the other one is going up by 45%!! How do you justify those increases. I can understand if my claims went into the the R100,000 of Rands, but the highest claim paid out was R22,000 and the few other under R10,000. Outsurance have now lost my business and I will never go back!!! Pathetic