Safety Measurement System

Measure vs. Percentile

Carrier violations or crashes are weighted by time and severity to produce a measure for that carrier in each BASIC. The measure is then used to assign that carrier to a percentile rank containing carriers’ information in similar safety event groups. Expand for more information.

Carrier violations or crashes are weighted by time and severity to produce a measure for that carrier in each BASIC. The measure only considers individual performance based on 24 months of data, with a measure of 0 indicating best performance. The measure is then used to assign that carrier to a percentile rank containing carriers’ information in similar safety event groups. The graph below shows how the carrier’s measure correlates with its percentile rank over a selected period of time.

Measure

Percentile

Measure	Percentile
0	0
0.06	1
0.07	2
0.08	3
0.09	4
0.10	5
0.10	6
0.11	7
0.13	8
0.13	9
0.15	10
0.17	11
0.18	12
0.20	13
0.23	14
0.26	15
0.29	16
0.33	17
0.36	18
0.38	19
0.41	20
0.45	21
0.47	22
0.51	23
0.52	24
0.55	25
0.57	26
0.59	27
0.61	28
0.63	29
0.65	30
0.67	31
0.70	32
0.72	33
0.75	34
0.76	35
0.78	36
0.81	37
0.83	38
0.85	39
0.87	40
0.90	41
0.91	42
0.94	43
1.01	44
1.02	45
1.03	46
1.05	47
1.10	48
1.11	49
1.12	50
1.17	51
1.21	52
1.24	53
1.26	54
1.28	55
1.34	56
1.37	57
1.40	58
1.43	59
1.44	60
1.51	61
1.54	62
1.58	63
1.63	64
1.67	65
1.68	66
1.75	67
1.80	68
1.84	69
1.88	70
1.96	71
2.01	72
2.03	73
2.09	74
2.15	75
2.21	76
2.25	77
2.31	78
2.38	79
2.50	80
2.52	81
2.61	82
2.73	83
2.82	84
2.89	85
3.02	86
3.10	87
3.26	88
3.34	89
3.53	90
3.72	91
3.90	92
4.11	93
4.34	94
4.67	95
5.07	96
5.67	97
6.40	98
7.73	99
17.20	100