# WBS, severity, frequency
#concept
2,1,0
2,2,7
2,3,54
2,4,11
2,5,2
# requirements
3,1,1
3,2,70
3,3,874
3,4,435
3,5,133
# design
4,1,0
4,2,18
4,3,275
4,4,129
4,5,25
# implement
5,1,1
5,2,59 
5,3,364
5,4,282
5,5,76
# test
6,1,1
6,2,10
6,3,361
6,4,271
6,5,41