(ShareCast News) - Insurance business Novae posted a 20% fall in first half pre-tax profits due to foreign exchange movements.The company posted first half profit before tax of £16.9m, a 20.6% decline year-on-year after adverse foreign exchange movements had a £12.1m impact on the balance sheet.The group indicated that had it not been for the currency valuations, it would have posted profit before tax up 28.3% on the year before, to £29m.The insurer improved gross written premiums by 27%, to £463.1m, while net tangible asset value per share was down 4.1% to 500.2p, which the company said reflected profits and payment of final and special dividends in May.The board declared an interim dividend of 7.3p, which was a 10.6% increase on last year's interim dividend.Novae said headwinds such as pressure on premium rates, low investment returns and increased regulation would persist.Novae shares were down 0.34% to 730.50p at 1608 BST on Wednesday.