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
0.06	1
0.09	2
0.12	3
0.15	4
0.17	5
0.20	6
0.22	7
0.26	8
0.29	9
0.32	10
0.34	11
0.37	12
0.40	13
0.43	14
0.46	15
0.50	16
0.53	17
0.56	18
0.60	19
0.63	20
0.66	21
0.70	22
0.72	23
0.76	24
0.79	25
0.83	26
0.87	27
0.91	28
0.94	29
0.98	30
1.03	31
1.07	32
1.11	33
1.16	34
1.20	35
1.25	36
1.30	37
1.35	38
1.41	39
1.45	40
1.51	41
1.58	42
1.65	43
1.72	44
1.78	45
1.85	46
1.92	47
1.97	48
2.04	49
2.11	50
2.19	51
2.27	52
2.37	53
2.48	54
2.57	55
2.66	56
2.79	57
2.88	58
3.00	59
3.11	60
3.23	61
3.35	62
3.47	63
3.63	64
3.78	65
3.96	66
4.13	67
4.34	68
4.53	69
4.75	70
4.96	71
5.25	72
5.60	73
5.82	74
6.07	75
6.33	76
6.68	77
7.01	78
7.44	79
7.94	80
8.31	81
8.94	82
9.57	83
10.16	84
10.68	85
11.47	86
12.21	87
13.08	88
14.35	89
15.40	90
16.68	91
18.89	92
21.00	93
23.35	94
27.27	95
32.02	96
37.03	97
43.40	98
62.15	99
173.00	100