(Telecompaper) Vodafone Group reported a small slowdown in underlying revenue growth in its fiscal first quarter to June, but said it's on track with its cost savings efforts and full-year outlook. Total revenues dropped 4.9 percent to EUR 10.91 billion, hurt by the new accounting rules and negative currency effects. Organic service revenue was up 1.1 percent, or grew 0.3 percent based on the old accounting standards.