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
0.23	1
0.34	2
0.45	3
0.55	4
0.65	5
0.75	6
0.84	7
0.93	8
1.03	9
1.13	10
1.21	11
1.31	12
1.40	13
1.50	14
1.57	15
1.67	16
1.75	17
1.83	18
1.92	19
2.02	20
2.11	21
2.19	22
2.28	23
2.37	24
2.45	25
2.55	26
2.63	27
2.73	28
2.81	29
2.89	30
3.02	31
3.09	32
3.19	33
3.29	34
3.39	35
3.48	36
3.57	37
3.67	38
3.77	39
3.86	40
4.01	41
4.06	42
4.17	43
4.26	44
4.37	45
4.47	46
4.59	47
4.69	48
4.80	49
4.90	50
5.03	51
5.13	52
5.24	53
5.35	54
5.50	55
5.61	56
5.73	57
5.85	58
6.01	59
6.10	60
6.23	61
6.37	62
6.51	63
6.65	64
6.79	65
6.94	66
7.09	67
7.24	68
7.39	69
7.56	70
7.72	71
7.88	72
8.04	73
8.23	74
8.43	75
8.61	76
8.81	77
9.03	78
9.24	79
9.46	80
9.71	81
10.00	82
10.20	83
10.47	84
10.76	85
11.06	86
11.38	87
11.70	88
12.10	89
12.51	90
12.92	91
13.40	92
13.90	93
14.51	94
15.18	95
16.01	96
17.04	97
18.42	98
20.69	99
30.00	100