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
0.18	1
0.31	2
0.44	3
0.55	4
0.68	5
0.78	6
0.87	7
0.96	8
1.05	9
1.12	10
1.20	11
1.28	12
1.35	13
1.42	14
1.48	15
1.56	16
1.63	17
1.68	18
1.75	19
1.81	20
1.87	21
1.93	22
2.00	23
2.06	24
2.11	25
2.18	26
2.24	27
2.30	28
2.36	29
2.42	30
2.48	31
2.55	32
2.61	33
2.68	34
2.74	35
2.81	36
2.86	37
2.92	38
2.99	39
3.05	40
3.12	41
3.18	42
3.24	43
3.29	44
3.36	45
3.43	46
3.50	47
3.56	48
3.64	49
3.71	50
3.79	51
3.85	52
3.91	53
3.98	54
4.05	55
4.14	56
4.21	57
4.27	58
4.36	59
4.44	60
4.53	61
4.61	62
4.69	63
4.78	64
4.87	65
4.96	66
5.04	67
5.14	68
5.23	69
5.32	70
5.40	71
5.51	72
5.60	73
5.71	74
5.82	75
5.93	76
6.05	77
6.19	78
6.30	79
6.45	80
6.58	81
6.75	82
6.93	83
7.13	84
7.31	85
7.47	86
7.68	87
7.90	88
8.13	89
8.39	90
8.69	91
8.96	92
9.30	93
9.72	94
10.26	95
10.87	96
11.62	97
12.76	98
14.43	99
24.38	100