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
0.04	1
0.04	2
0.05	3
0.06	4
0.07	5
0.08	6
0.09	7
0.10	8
0.11	9
0.12	10
0.13	11
0.14	12
0.16	13
0.17	14
0.19	15
0.20	16
0.22	17
0.23	18
0.25	19
0.26	20
0.28	21
0.29	22
0.31	23
0.32	24
0.34	25
0.35	26
0.37	27
0.39	28
0.40	29
0.42	30
0.44	31
0.46	32
0.48	33
0.50	34
0.52	35
0.53	36
0.55	37
0.57	38
0.60	39
0.62	40
0.64	41
0.67	42
0.68	43
0.70	44
0.73	45
0.75	46
0.78	47
0.80	48
0.83	49
0.85	50
0.88	51
0.91	52
0.93	53
0.96	54
1.01	55
1.03	56
1.05	57
1.08	58
1.11	59
1.15	60
1.18	61
1.21	62
1.25	63
1.28	64
1.32	65
1.37	66
1.41	67
1.45	68
1.50	69
1.54	70
1.60	71
1.65	72
1.70	73
1.76	74
1.83	75
1.89	76
1.95	77
2.02	78
2.09	79
2.16	80
2.23	81
2.32	82
2.41	83
2.51	84
2.60	85
2.69	86
2.82	87
2.94	88
3.07	89
3.21	90
3.36	91
3.53	92
3.73	93
3.91	94
4.19	95
4.48	96
4.85	97
5.48	98
6.29	99
11.67	100