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
0.09	2
0.12	3
0.16	4
0.19	5
0.23	6
0.26	7
0.29	8
0.34	9
0.38	10
0.41	11
0.45	12
0.49	13
0.53	14
0.56	15
0.60	16
0.63	17
0.68	18
0.72	19
0.76	20
0.81	21
0.86	22
0.92	23
0.96	24
1.00	25
1.06	26
1.10	27
1.16	28
1.21	29
1.28	30
1.33	31
1.39	32
1.46	33
1.52	34
1.60	35
1.67	36
1.73	37
1.80	38
1.87	39
1.95	40
2.03	41
2.11	42
2.19	43
2.26	44
2.36	45
2.45	46
2.56	47
2.67	48
2.78	49
2.87	50
3.00	51
3.10	52
3.23	53
3.37	54
3.50	55
3.64	56
3.78	57
3.90	58
4.09	59
4.25	60
4.40	61
4.62	62
4.84	63
5.08	64
5.30	65
5.51	66
5.74	67
6.00	68
6.29	69
6.63	70
6.88	71
7.20	72
7.51	73
7.83	74
8.20	75
8.54	76
9.00	77
9.31	78
9.75	79
10.29	80
10.83	81
11.51	82
12.01	83
12.75	84
13.35	85
14.29	86
15.33	87
16.28	88
17.28	89
18.54	90
20.39	91
22.12	92
24.53	93
26.98	94
30.00	95
33.95	96
40.13	97
46.24	98
58.55	99
106.00	100