KELLER GROUP PLC ORD GBP0.10 revenue for the last year amounted to 2.97 B GBP, the most of which — 2.97 B GBP — came from its highest performing source at the moment, Specialist Geotechnical Services, the year earlier bringing 2.94 B GBP. The greatest contribution to the revenue figure was made by United States — last year it brought KELLER GROUP PLC ORD GBP0.10 1.64 B GBP, and the year before that — 1.76 B GBP.