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
0.33	1
0.49	2
0.61	3
0.71	4
0.83	5
0.92	6
1.02	7
1.10	8
1.19	9
1.27	10
1.35	11
1.43	12
1.50	13
1.59	14
1.67	15
1.74	16
1.80	17
1.88	18
1.95	19
2.02	20
2.10	21
2.17	22
2.24	23
2.31	24
2.39	25
2.47	26
2.54	27
2.63	28
2.70	29
2.78	30
2.86	31
2.94	32
3.00	33
3.10	34
3.18	35
3.27	36
3.36	37
3.46	38
3.55	39
3.64	40
3.73	41
3.82	42
3.92	43
4.03	44
4.14	45
4.25	46
4.34	47
4.45	48
4.57	49
4.67	50
4.80	51
4.92	52
5.06	53
5.18	54
5.30	55
5.45	56
5.59	57
5.74	58
5.90	59
6.04	60
6.24	61
6.40	62
6.57	63
6.75	64
6.94	65
7.12	66
7.33	67
7.60	68
7.81	69
8.03	70
8.32	71
8.61	72
8.95	73
9.21	74
9.50	75
9.86	76
10.17	77
10.50	78
11.00	79
11.38	80
11.87	81
12.34	82
12.89	83
13.45	84
14.00	85
14.75	86
15.45	87
16.26	88
17.34	89
18.33	90
19.57	91
21.01	92
22.75	93
24.88	94
27.27	95
30.53	96
34.67	97
40.10	98
50.20	99
174.00	100