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
0.07	1
0.10	2
0.13	3
0.15	4
0.18	5
0.20	6
0.23	7
0.25	8
0.28	9
0.32	10
0.35	11
0.37	12
0.40	13
0.44	14
0.47	15
0.51	16
0.54	17
0.57	18
0.61	19
0.63	20
0.67	21
0.70	22
0.73	23
0.77	24
0.80	25
0.83	26
0.87	27
0.91	28
0.95	29
0.99	30
1.03	31
1.07	32
1.12	33
1.17	34
1.21	35
1.25	36
1.31	37
1.35	38
1.39	39
1.45	40
1.50	41
1.55	42
1.61	43
1.68	44
1.78	45
1.83	46
1.91	47
2.00	48
2.06	49
2.17	50
2.22	51
2.31	52
2.40	53
2.53	54
2.63	55
2.73	56
2.83	57
2.93	58
3.07	59
3.22	60
3.36	61
3.51	62
3.63	63
3.77	64
3.93	65
4.07	66
4.23	67
4.43	68
4.60	69
4.80	70
5.01	71
5.27	72
5.47	73
5.86	74
6.21	75
6.56	76
6.84	77
7.21	78
7.62	79
8.00	80
8.33	81
8.79	82
9.52	83
10.00	84
10.71	85
11.38	86
12.04	87
13.22	88
14.37	89
15.69	90
17.33	91
18.82	92
21.07	93
23.76	94
26.50	95
30.57	96
36.42	97
44.62	98
63.63	99
150.00	100