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
0.17	1
0.32	2
0.44	3
0.53	4
0.62	5
0.72	6
0.81	7
0.88	8
0.95	9
1.03	10
1.11	11
1.18	12
1.25	13
1.31	14
1.38	15
1.44	16
1.51	17
1.57	18
1.63	19
1.69	20
1.76	21
1.81	22
1.88	23
1.94	24
2.00	25
2.06	26
2.13	27
2.18	28
2.24	29
2.30	30
2.37	31
2.42	32
2.48	33
2.54	34
2.59	35
2.64	36
2.70	37
2.76	38
2.82	39
2.88	40
2.94	41
3.00	42
3.07	43
3.14	44
3.20	45
3.27	46
3.34	47
3.41	48
3.48	49
3.54	50
3.61	51
3.68	52
3.75	53
3.82	54
3.90	55
3.98	56
4.06	57
4.13	58
4.21	59
4.28	60
4.36	61
4.44	62
4.53	63
4.61	64
4.69	65
4.78	66
4.88	67
4.97	68
5.05	69
5.15	70
5.24	71
5.34	72
5.45	73
5.55	74
5.65	75
5.77	76
5.88	77
6.00	78
6.13	79
6.27	80
6.41	81
6.56	82
6.71	83
6.87	84
7.05	85
7.25	86
7.47	87
7.65	88
7.88	89
8.10	90
8.36	91
8.67	92
8.98	93
9.40	94
9.88	95
10.39	96
11.11	97
12.18	98
13.81	99
25.90	100