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
0.24	1
0.38	2
0.50	3
0.60	4
0.72	5
0.83	6
0.93	7
1.03	8
1.14	9
1.25	10
1.34	11
1.44	12
1.55	13
1.64	14
1.75	15
1.84	16
2.00	17
2.04	18
2.15	19
2.26	20
2.34	21
2.45	22
2.55	23
2.64	24
2.75	25
2.85	26
2.96	27
3.05	28
3.16	29
3.26	30
3.38	31
3.47	32
3.58	33
3.68	34
3.78	35
3.89	36
4.02	37
4.09	38
4.20	39
4.30	40
4.42	41
4.53	42
4.64	43
4.76	44
4.86	45
5.01	46
5.10	47
5.21	48
5.34	49
5.45	50
5.58	51
5.70	52
5.84	53
6.01	54
6.08	55
6.21	56
6.35	57
6.50	58
6.63	59
6.77	60
6.90	61
7.03	62
7.19	63
7.34	64
7.47	65
7.64	66
7.80	67
8.00	68
8.13	69
8.29	70
8.50	71
8.68	72
8.86	73
9.04	74
9.25	75
9.46	76
9.69	77
9.91	78
10.13	79
10.38	80
10.64	81
10.90	82
11.21	83
11.50	84
11.77	85
12.09	86
12.43	87
12.80	88
13.21	89
13.64	90
14.11	91
14.63	92
15.21	93
15.88	94
16.62	95
17.51	96
18.61	97
20.00	98
22.18	99
30.00	100