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
0.16	1
0.30	2
0.44	3
0.56	4
0.67	5
0.76	6
0.86	7
0.95	8
1.03	9
1.11	10
1.19	11
1.26	12
1.34	13
1.42	14
1.48	15
1.55	16
1.63	17
1.69	18
1.76	19
1.83	20
1.90	21
1.96	22
2.02	23
2.09	24
2.15	25
2.21	26
2.27	27
2.33	28
2.40	29
2.46	30
2.52	31
2.58	32
2.65	33
2.72	34
2.78	35
2.84	36
2.91	37
2.97	38
3.04	39
3.11	40
3.16	41
3.23	42
3.30	43
3.37	44
3.43	45
3.50	46
3.57	47
3.64	48
3.71	49
3.78	50
3.85	51
3.91	52
3.98	53
4.05	54
4.14	55
4.21	56
4.30	57
4.38	58
4.45	59
4.53	60
4.60	61
4.70	62
4.78	63
4.87	64
4.96	65
5.04	66
5.12	67
5.22	68
5.33	69
5.44	70
5.55	71
5.64	72
5.74	73
5.85	74
5.96	75
6.08	76
6.21	77
6.34	78
6.49	79
6.63	80
6.77	81
6.93	82
7.07	83
7.27	84
7.43	85
7.63	86
7.81	87
8.06	88
8.29	89
8.54	90
8.78	91
9.13	92
9.49	93
9.92	94
10.39	95
10.96	96
11.75	97
12.85	98
14.51	99
28.00	100