It has been a rough week for the companies comprising our Vendors segment – tumbling 8.78%. Both the Operators and Indexes segments fell, but by nowhere near as much. Since we began tracking, the Vendors segment is up 63.27% – compared to a loss of 16.71% for the Operators, and a fall of 5.83% for the Indexes. There were only four positive vendor gains this week. Nokia, despite posting challenging results, was up 11.43% – the best performer. Arch-rival Ericsson was second, with a 7.58% gain, while Amdocs took third, with a 1.01% gain. This left NetScout in fourth, with just a 0.51% improvement. The silicon stocks took a beating, driving the segment down. The worst performer this week was…