Sec -2.0 or worse will be attacked in 1.0 systems Sec -2.5 or worse will be attacked in 0.9 systems Sec -3.0 or worse will be attacked in 0.8 systems Sec -3.5 or worse will be attacked in 0.7 systems Sec -4.0 or worse will be attacked in 0.6 systems Sec -4.5 or worse will be attacked in 0.5 systems