SOLNA, Sweden--(BUSINESS WIRE)--Regulatory News: ICA Gruppen (STO:ICA) Sales in the Swedish ICA stores rose by 3.5% in May 2015 compared with the corresponding month last year. Sales in like-for-like stores increased by 2.8%.   May-15   January - May 2015 Store sales, excl. VAT SEKm   Change all stores   Change like-for-like SEKm   Change all stores   Change like-for-like Maxi ICA Stormarknad 2,826 6.10% 4.0% 13,063 6.00% 3.70% ICA Kvantum 2,239 4.20% 3.0% 10,623 5.20% 3.40% ICA Supermarket 2,7