ProAssurance (NYSE: PRA) shares soared 12.6% in the last trading session to close at $13.16. The move was backed by solid volume with far more shares changing hands than in a normal session. This compares to the stock's 4.2% loss over the past four weeks. Increased optimism around the accelerated growth in new business is driving the stock. This is expected to boost premium levels in the near future. The company's Specialty P&C Segment and Workers' Compensation Insurance businesses are likely to be key growth drivers. Additionally, the company's focus on cost-control measures is expected to improve its margins, ...