Vouchers and Christmas hampers supplier Park Group saw its share price take a tumble after reporting a fall in revenue as profits swung into the red.Revenues for the half year fell from £50.9m to £46m on a like-for-like basis. Meanwhile, rising costs led to a pre-tax loss of £4.4m, compared with a profit of £0.5m the year before.. Chairman Peter Johnson maintained a positive outlook, saying: "The second half of the year has started well in the corporate and consumer businesses with orders running ahead of the same time last year. There is no doubt that the prepaid card and our application of online technologies is transforming Park and offers exciting growth opportunities in both existing and new market areas. "The outlook for Park is encouraging; the dividend increase reflects this confidence. Park is in a strong position and we anticipate another year of growth."The company saw an 8% rise in customer numbers during the period, while customer order value was also significantly ahead of the previous year at £417 (2010: £401). The firm is set to increase the interim dividend from 0.5p to 0.525p per share. Cash at the end of the period fell to £3.2m, compared to £11.3m at the same date the previous year. The share price fell 7.66% to 51.25p by 16:33. NR