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
0.29	1
0.44	2
0.55	3
0.64	4
0.73	5
0.82	6
0.89	7
0.97	8
1.06	9
1.14	10
1.21	11
1.29	12
1.36	13
1.42	14
1.50	15
1.57	16
1.65	17
1.72	18
1.81	19
1.88	20
1.95	21
2.03	22
2.10	23
2.17	24
2.25	25
2.33	26
2.41	27
2.50	28
2.58	29
2.65	30
2.73	31
2.81	32
2.89	33
3.00	34
3.08	35
3.17	36
3.27	37
3.36	38
3.45	39
3.55	40
3.65	41
3.75	42
3.85	43
3.96	44
4.06	45
4.18	46
4.29	47
4.43	48
4.56	49
4.68	50
4.80	51
4.93	52
5.06	53
5.19	54
5.32	55
5.46	56
5.62	57
5.78	58
6.00	59
6.14	60
6.33	61
6.50	62
6.70	63
6.91	64
7.08	65
7.30	66
7.50	67
7.72	68
8.00	69
8.25	70
8.50	71
8.75	72
9.04	73
9.43	74
9.77	75
10.06	76
10.48	77
10.86	78
11.31	79
11.80	80
12.28	81
12.78	82
13.28	83
13.92	84
14.55	85
15.32	86
16.22	87
17.17	88
18.03	89
19.24	90
20.72	91
22.25	92
24.04	93
26.17	94
29.00	95
32.10	96
36.99	97
44.02	98
56.06	99
176.39	100