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
0.17	1
0.32	2
0.45	3
0.56	4
0.67	5
0.78	6
0.88	7
0.96	8
1.04	9
1.12	10
1.19	11
1.26	12
1.35	13
1.42	14
1.49	15
1.56	16
1.62	17
1.69	18
1.76	19
1.82	20
1.88	21
1.95	22
2.02	23
2.08	24
2.15	25
2.21	26
2.27	27
2.34	28
2.39	29
2.46	30
2.53	31
2.58	32
2.65	33
2.71	34
2.78	35
2.84	36
2.90	37
2.97	38
3.03	39
3.10	40
3.16	41
3.21	42
3.28	43
3.34	44
3.41	45
3.48	46
3.54	47
3.61	48
3.68	49
3.75	50
3.82	51
3.90	52
3.97	53
4.05	54
4.13	55
4.20	56
4.28	57
4.35	58
4.43	59
4.51	60
4.59	61
4.66	62
4.74	63
4.82	64
4.91	65
5.00	66
5.10	67
5.18	68
5.27	69
5.38	70
5.48	71
5.57	72
5.67	73
5.78	74
5.90	75
6.03	76
6.16	77
6.30	78
6.44	79
6.58	80
6.72	81
6.87	82
7.05	83
7.21	84
7.37	85
7.58	86
7.78	87
8.01	88
8.26	89
8.56	90
8.82	91
9.15	92
9.49	93
9.86	94
10.39	95
10.87	96
11.59	97
12.63	98
14.23	99
23.53	100