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
0.33	1
0.43	2
0.54	3
0.60	4
0.68	5
0.78	6
0.86	7
0.95	8
1.00	9
1.07	10
1.10	11
1.14	12
1.19	13
1.24	14
1.28	15
1.32	16
1.37	17
1.42	18
1.46	19
1.51	20
1.56	21
1.60	22
1.64	23
1.66	24
1.70	25
1.74	26
1.79	27
1.84	28
1.87	29
1.92	30
1.96	31
2.02	32
2.06	33
2.11	34
2.16	35
2.20	36
2.24	37
2.28	38
2.32	39
2.39	40
2.44	41
2.48	42
2.52	43
2.57	44
2.62	45
2.66	46
2.70	47
2.76	48
2.80	49
2.83	50
2.85	51
2.88	52
2.91	53
2.97	54
3.02	55
3.07	56
3.13	57
3.18	58
3.26	59
3.29	60
3.34	61
3.40	62
3.48	63
3.52	64
3.59	65
3.65	66
3.72	67
3.81	68
3.88	69
3.98	70
4.10	71
4.24	72
4.32	73
4.42	74
4.50	75
4.62	76
4.71	77
4.81	78
4.91	79
5.06	80
5.17	81
5.40	82
5.49	83
5.67	84
5.89	85
6.11	86
6.38	87
6.69	88
7.18	89
7.57	90
8.00	91
8.56	92
9.09	93
9.90	94
10.47	95
11.77	96
13.30	97
16.86	98
23.40	99
131.00	100