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
0.03	1
0.04	2
0.05	3
0.05	4
0.06	5
0.07	6
0.08	7
0.09	8
0.10	9
0.11	10
0.12	11
0.13	12
0.14	13
0.16	14
0.17	15
0.19	16
0.20	17
0.22	18
0.23	19
0.24	20
0.26	21
0.28	22
0.29	23
0.31	24
0.32	25
0.34	26
0.35	27
0.37	28
0.39	29
0.41	30
0.43	31
0.44	32
0.46	33
0.48	34
0.51	35
0.52	36
0.54	37
0.56	38
0.59	39
0.61	40
0.63	41
0.65	42
0.68	43
0.70	44
0.72	45
0.74	46
0.77	47
0.79	48
0.81	49
0.84	50
0.86	51
0.89	52
0.91	53
0.94	54
0.97	55
1.01	56
1.04	57
1.06	58
1.09	59
1.13	60
1.16	61
1.20	62
1.24	63
1.28	64
1.32	65
1.36	66
1.40	67
1.45	68
1.50	69
1.55	70
1.60	71
1.65	72
1.70	73
1.76	74
1.82	75
1.89	76
1.96	77
2.04	78
2.10	79
2.19	80
2.26	81
2.34	82
2.43	83
2.53	84
2.62	85
2.73	86
2.85	87
2.97	88
3.11	89
3.25	90
3.43	91
3.62	92
3.86	93
4.06	94
4.34	95
4.66	96
5.11	97
5.69	98
6.54	99
11.65	100