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
0.29	1
0.45	2
0.57	3
0.67	4
0.74	5
0.83	6
0.91	7
1.00	8
1.07	9
1.15	10
1.23	11
1.30	12
1.38	13
1.45	14
1.53	15
1.60	16
1.68	17
1.75	18
1.83	19
1.90	20
1.97	21
2.05	22
2.13	23
2.20	24
2.29	25
2.38	26
2.45	27
2.53	28
2.60	29
2.68	30
2.76	31
2.84	32
2.92	33
3.00	34
3.10	35
3.19	36
3.28	37
3.38	38
3.46	39
3.55	40
3.65	41
3.75	42
3.85	43
3.96	44
4.06	45
4.17	46
4.28	47
4.39	48
4.54	49
4.67	50
4.80	51
4.95	52
5.08	53
5.23	54
5.37	55
5.51	56
5.66	57
5.81	58
6.00	59
6.17	60
6.35	61
6.50	62
6.69	63
6.91	64
7.13	65
7.34	66
7.55	67
7.80	68
8.00	69
8.29	70
8.53	71
8.83	72
9.14	73
9.47	74
9.81	75
10.16	76
10.51	77
11.00	78
11.41	79
11.96	80
12.38	81
12.89	82
13.43	83
14.01	84
14.71	85
15.46	86
16.22	87
17.10	88
18.18	89
19.35	90
20.91	91
22.48	92
24.28	93
26.38	94
28.84	95
32.02	96
36.09	97
44.00	98
56.39	99
176.39	100