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
0.01	1
0.02	2
0.02	3
0.03	4
0.03	5
0.04	6
0.04	7
0.05	8
0.06	9
0.06	10
0.07	11
0.08	12
0.08	13
0.09	14
0.10	15
0.11	16
0.12	17
0.13	18
0.13	19
0.14	20
0.15	21
0.16	22
0.17	23
0.18	24
0.19	25
0.20	26
0.21	27
0.22	28
0.23	29
0.24	30
0.25	31
0.26	32
0.27	33
0.28	34
0.30	35
0.31	36
0.32	37
0.33	38
0.34	39
0.36	40
0.37	41
0.38	42
0.39	43
0.41	44
0.42	45
0.44	46
0.45	47
0.47	48
0.48	49
0.50	50
0.51	51
0.53	52
0.54	53
0.56	54
0.58	55
0.59	56
0.61	57
0.63	58
0.65	59
0.67	60
0.69	61
0.72	62
0.74	63
0.76	64
0.79	65
0.81	66
0.83	67
0.86	68
0.89	69
0.92	70
0.95	71
0.99	72
1.02	73
1.06	74
1.10	75
1.14	76
1.19	77
1.24	78
1.28	79
1.33	80
1.38	81
1.43	82
1.49	83
1.55	84
1.62	85
1.69	86
1.78	87
1.87	88
1.95	89
2.06	90
2.18	91
2.32	92
2.46	93
2.66	94
2.89	95
3.18	96
3.55	97
4.09	98
4.94	99
8.76	100