By Amber Murray London-listed software provider Kainos has reported a drop in revenue amid a tough trading environment and delays to public investment after the general election. Kainos, which is a key supplier to the NHS, reported revenue of £183.1m in the first half of the year, down five per cent year on year. Profit before tax rose 11 per cent to £34.2m, while adjusted diluted earnings per share rose two per cent to 22.5p. “Our services businesses faced a tougher environment in the first half of the year in a generally soft market, and we remain cautious about our prospects for the remaind…