By Martin Coulter LONDON (Reuters) -U.S. venture capital firm Andreessen Horowitz has backed London-based insurance startup Hyperexponential in a $73 million funding round, the insurance software company said on Thursday. Founded in 2017, Hyperexponential provides insurance companies with mathematical modeling software, allowing them to price policies based on a wide range of data. The funding round was led by Battery Ventures. The firm’s funding announcement comes during a slump in investment in Europe’s technology sector, which is expected to have plunged to $45 billion in 2023 from $82 bill…