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
0.34	2
0.48	3
0.61	4
0.72	5
0.85	6
0.95	7
1.04	8
1.12	9
1.21	10
1.30	11
1.38	12
1.46	13
1.53	14
1.60	15
1.68	16
1.75	17
1.83	18
1.90	19
1.97	20
2.05	21
2.12	22
2.19	23
2.27	24
2.34	25
2.41	26
2.48	27
2.56	28
2.63	29
2.70	30
2.76	31
2.83	32
2.90	33
2.96	34
3.03	35
3.11	36
3.17	37
3.24	38
3.31	39
3.38	40
3.45	41
3.53	42
3.61	43
3.69	44
3.76	45
3.83	46
3.91	47
3.98	48
4.06	49
4.14	50
4.21	51
4.30	52
4.38	53
4.46	54
4.53	55
4.60	56
4.67	57
4.76	58
4.85	59
4.93	60
5.01	61
5.10	62
5.19	63
5.29	64
5.39	65
5.50	66
5.59	67
5.68	68
5.79	69
5.91	70
6.03	71
6.13	72
6.26	73
6.38	74
6.49	75
6.61	76
6.77	77
6.91	78
7.05	79
7.20	80
7.37	81
7.52	82
7.71	83
7.89	84
8.08	85
8.31	86
8.51	87
8.72	88
8.95	89
9.22	90
9.52	91
9.81	92
10.17	93
10.61	94
11.12	95
11.71	96
12.46	97
13.60	98
15.51	99
25.56	100