(Sharecast News) - Johnson Services turned in another "consistently strong performance" on Tuesday, as its strategy of driving growth organically, coupled with selective acquisitions, started to bear some fruits.Throughout the first half of its trading year, Johnson saw revenues increase 10.3% to £152.2m, leading to a pre-tax profit of £18.2m for the period - an 8.3% improvement itself.Earnings per share jumped 8.1% to 4.0p and the group increased its interim dividend by 11.1% to 1.0p per share.In order to support demand from the firm's strong organic growth, Johnson made "significant capital investment" into its production capacity at selected sites during the period, resulting in net debt expanding from £90m to £91.2m.The AIM-listed firm now expects full-year results to be "slightly ahead" of current market expectations.Chris Sander, chief executive of Johnson, said: "Recent organic growth and margin performance gives us confidence in the outlook for the second half of 2018. As a result, we expect results for the full year to be slightly ahead of current market expectations."Elsewhere, Johnson wrapped up its acquisition of HORECA linen business, South West Laundry, on Friday, extending the firm's coverage to South West England.As of 1320 BST, Johnson shares had moved ahead 2.94% to 143.60p.