A growth in client numbers at spread betting titan IG Group pushed third quarter revenues higher. Group revenue in the three months to end-February rose to around £76m from £69m in the corresponding period a year earlier, despite the group seeing only a fractional increase in revenue per client.Volatility through the quarter was generally low and was particularly subdued in December and for much of February, but increased noticeably towards the end of February.The group's UK financial business saw revenue improve to £39.9m from £37.2m a year earlier, but the Australian business saw revenue decline 3% to £10.4m from £10.7m a year earlier, despite a 6% increase in the number of active clients.Active client numbers across the group's European offices grew by 33% year on year and revenue increased by 18% from £12.1m to £14.2m.The troublesome Japanese business saw revenue dive 11% to £4.5m from £5m, with both revenue per client and the number of active clients hitting the skids, after local leverage restrictions were introduced in August 2010 and January 2011.Singapore picked up some of the slack, with revenue surging 46% to £3.8m, up from £2.6m a year earlier. The group's Sports business achieved revenue of £2.0m, up from £1.3m in the prior year, a 52% increase.Management warned that comparatives for the final quarter of the financial year get tougher, but the recent civil unrest in Africa and the Middle East has increased market volatility and has thus encouraged betters to trade more frequently."Despite muted volatility levels for much of the period the group has continued to achieve good growth in its active client base. This, combined with its market and technology leadership and continued investment in the business, leave the group well placed to deliver further long-term profitable growth," the company statement concluded.