International Public Partnerships (INPP) raised its half-year dividend by 2.5 per cent to 3.075p on the back of net asset value (NAV) growth.NAV grew 7% to £921.3m in the first half compared to a year earlier driven by strong performance across the infrastructure investment company's portfolio of 122 assets.Underlying projects generated £30.6m of gross cash flow, up from the prior year's £22.2m. International Financial Reporting Standards (IFRS) pre-tax profit came in at £7.2m, down from £19.4m the previous year. During the period, the group made £8.5m of additional investments, including a 25% stake in the Alberta Schools project and £1m in the existing Building Schools for the Future private finance initiative project in England. The company also completed construction on the Liverpool Central Library and Archive project."Once again, INPP has announced a healthy financial performance during the first half, providing investors with stability in a fluctuating market," said Chairman, Keith Dorrian."INPP's geographic reach and disciplined approach to acquisitions, combined with the Investment Manager's origination capabilities, positions the company well as pricing pressure in the UK secondary market continues."Shares fell 0.23% to 132.70p at 10:27 on Thursday.RD