(ShareCast News) - Managed services and staffing company Impellam Group posted an increase in interim profit, driven by a sharp hike in revenue.The London-listed group reported a 40.5% year-on-year in pre-tax profit to £20.1m, on the back of a 36% increase in revenue to £831.6m, which was partly driven by the acquisitions of Lorien and Career Teachers.Both businesses have been fully integrated and are performing ahead of the company's expectations, Impellam said, adding its managed services and staffing divisions delivered strong performances throughout the period.The managed services division saw its UK revenue surge 85% year-on-year on the back of acquisitions and rose 7.5% on a like-for-like basis.Meanwhile, revenue in the staffing division rose 18% in the UK but declined slightly in the US, although the company said it was confident of improving trading in the region.Impellam lifted its interim dividend 12% to 7p.On Thursday, Impellam shares closed up 9.92% to 802.40p.