(Sharecast News) - Shares in online retailer Mysale Group slumped on Tuesday after the company reported a deepened loss before tax alongside the resignation of chief financial officer Andrew Dingle.Dingle, who guided the company through its initial public offering in 2014, steps down from the board with immediate effect and will leave Mysale at the end of October to pursue other opportunities.Group financial controller Maarit Piisila will take on Dingle's responsibilities during a handover period lasting until Dingle's exit.Meanwhile, for the year ended 30 June the company registered a loss before tax of AU$1.7m, 9% increase in loss over the year before, after being slapped with a AU$1.4m charge relating to the purchase of Identity Direct, a personalised book retailer in Australia and New Zealand.Excluding one-off costs, the company achieved pre-tax profit of AU$4.9m, up by 50% from the previous year, as a result of a 9% increase in revenue to AU$292.2m and another 9% in active customer base to 1m, following strong merchandising.Carl Jackson, chief executive of Mysale, said: ''We are very pleased to deliver another set of record results, with significant increases in both our sales and profit performance for the year, demonstrating the strategic progress we have made to harness our technology platform, increase customer engagement and drive growth."Average order values, basket size and order frequency have also grown, as has the AIM traded company's mobile platform, through which the majority of orders were placed.With Mysale's online platform "strengthened" and the company's peak trading period still ahead, the board expects underlying EBITDA for the year to fall in line with market expectations.Mysale's shares were down 15.18% at 41.90p at 0856 BST.