Just a simple question: what does the "M" in MvA stand for. I'm assuming "A" is average. I could not find the answer on the web. Thanks. Martino --------------------------------------- Martino Barenco CoMPLEX 4, Stephenson Way London NW1 2HE Tel.: +44 20 7679 5088 Fax.: +44 20 7679 5052 (please specify "CoMPLEX") Email: m.barenco at ucl.ac.uk