(ShareCast News) - International online marketing agency BrainJuicer said revenue was up 4% over the first half of the year, but pre-tax profit would be 25% lower than 2014.The research firm said sales of its core products, which equate to 90% of its business, were up by 7%.BrainJuicer said its main markets experienced contrasting fortunes, with the US delivering strong growth but UK sales below the same period last year."Overheads grew faster than revenue during the half, as the business continued to invest for future growth," the company said in a statement.The agency said it was still on track to meet profit expectations for the full year, because it typically generated the bulk of its profit in the second half of the year.At the end of June 2015 BrainJuicer recorded a cash balance of £5.3m, after returning £0.4m to shareholders during the half year by way of dividends.Canaccord Genuity kept its rating for the stock at 'buy' and held a price target of 495p.Analyst Simon Davies said while revenue visibility was limited, it was confident the agency would meet full year estimates.Davies said the UK sales decline was disappointing, but noted BrainJuicer had recorded consistent growth over a number of years."While a sales decline in the UK is somewhat disappointing, overall the group's core quantitative products have continued to grow and margins have improved."The group's financial position remains strong, with £5.3m of cash on the balance sheet which could potentially fund bolt-on acquisitions, and growth outside the UK has remained encouraging."Shares in BrainJuicer slid 3.13% to 402.50p on Thursday at 0948 BST.