(Sharecast News) - Online trading platform Plus500 reported a surge in first-half earnings on Monday as geopolitical events led to higher-than-expected market volatility, although it cautioned that the performance was unlikely to be repeated in the second half.In the six months to 30 June, earnings before interest, taxes, depreciation and amortisation rose 195% to $349m, as revenue jumped 147% to $465.5m. In addition, earnings per share during the period increased to $2.30 from $0.79 in the first half of last year. As well as increased market volatility, the company highlighted very active trading activity in the first quarter due to high levels of trading of cryptocurrency contracts-for-difference.Average revenue per user was up 12% to $1,873, while new customer numbers grew 75% to 94,148 and active customer numbers were up 121% to a record 248,564.Plus500 said third-quarter trading to date is in line with market expectations and the group is on track to meet current market views for 2018.However, the company said it's unlikely that the "exceptional" performance of the first half will be repeated and that the impact of rule changes will potentially affect less than half of EEA revenues (30% of group revenues) in the short term.Chief executive officer Asaf Elimelech said: "We have had a very successful first half with two major milestones; another record set of first half results including an exceptional first quarter performance and completion of our move up to the main market. The strong financial performance has enabled us to declare a very significant increase in shareholders returns by declaring a generous interim dividend."We have also made strong progress with our international diversification, within and outside the EEA, driven by our strong brand and new licences - Plus500 is now the biggest CFD broker in the UK, Germany, Spain and Australia according to Investment Trends,9 we grew our Active Customers in Australia fivefold and started operating in Singapore."Plus500 has implemented the recent regulatory changes and we anticipate an increased number of EPCs within European jurisdictions, complementing our growing activity outside the EEA."