Zurich Insurance reported net profit of 3.5 billion dollar for the first half of the year, up 14 percent from the same period a year earlier. Operating profit increased at a similar pace, rising from 4.2 billion dollar to 4.8 billion dollar, according to the results published on Thursday. Lower Premiums for Corporate ClientsIn the property and casualty business, gross written premiums increased 7 percent to 29.9 billion dollar. Overall, gross written premiums increased 1 percent to 19.5 billion dollar. Farmers Exchanges in the US also delivered growth, with gross written premiums rising 4 percent to 15.6 billion dollar.