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
0.30	1
0.47	2
0.58	3
0.68	4
0.78	5
0.87	6
0.95	7
1.04	8
1.12	9
1.19	10
1.27	11
1.35	12
1.42	13
1.50	14
1.58	15
1.66	16
1.73	17
1.80	18
1.87	19
1.96	20
2.03	21
2.11	22
2.19	23
2.26	24
2.34	25
2.41	26
2.49	27
2.56	28
2.64	29
2.72	30
2.81	31
2.88	32
2.99	33
3.07	34
3.16	35
3.25	36
3.34	37
3.44	38
3.55	39
3.65	40
3.75	41
3.86	42
3.96	43
4.06	44
4.16	45
4.27	46
4.38	47
4.50	48
4.62	49
4.74	50
4.86	51
5.00	52
5.12	53
5.25	54
5.40	55
5.53	56
5.70	57
5.86	58
6.00	59
6.20	60
6.38	61
6.56	62
6.74	63
6.95	64
7.17	65
7.40	66
7.62	67
7.89	68
8.13	69
8.38	70
8.63	71
8.90	72
9.23	73
9.53	74
9.86	75
10.23	76
10.66	77
11.01	78
11.50	79
12.00	80
12.50	81
13.00	82
13.57	83
14.25	84
15.00	85
15.64	86
16.49	87
17.36	88
18.34	89
19.51	90
20.78	91
22.31	92
24.00	93
25.84	94
28.57	95
31.58	96
35.64	97
41.43	98
54.05	99
146.00	100