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
0.08	1
0.13	2
0.18	3
0.23	4
0.26	5
0.30	6
0.33	7
0.38	8
0.41	9
0.45	10
0.49	11
0.53	12
0.57	13
0.61	14
0.64	15
0.70	16
0.74	17
0.78	18
0.82	19
0.86	20
0.90	21
0.95	22
1.00	23
1.05	24
1.09	25
1.14	26
1.19	27
1.25	28
1.29	29
1.35	30
1.41	31
1.46	32
1.50	33
1.59	34
1.65	35
1.70	36
1.77	37
1.83	38
1.90	39
1.97	40
2.03	41
2.11	42
2.18	43
2.25	44
2.34	45
2.42	46
2.53	47
2.62	48
2.72	49
2.81	50
2.94	51
3.04	52
3.14	53
3.26	54
3.36	55
3.48	56
3.60	57
3.71	58
3.87	59
4.00	60
4.17	61
4.34	62
4.50	63
4.68	64
4.88	65
5.10	66
5.33	67
5.55	68
5.79	69
6.00	70
6.29	71
6.51	72
6.78	73
7.12	74
7.50	75
7.80	76
8.10	77
8.50	78
8.92	79
9.34	80
9.70	81
10.11	82
10.73	83
11.27	84
11.90	85
12.47	86
13.33	87
14.02	88
14.99	89
16.02	90
17.14	91
18.34	92
20.12	93
22.55	94
25.14	95
29.09	96
34.04	97
41.00	98
50.86	99
114.00	100