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
0.02	1
0.02	2
0.02	3
0.03	4
0.04	5
0.04	6
0.05	7
0.05	8
0.06	9
0.07	10
0.08	11
0.08	12
0.09	13
0.10	14
0.11	15
0.11	16
0.12	17
0.13	18
0.14	19
0.15	20
0.16	21
0.17	22
0.18	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
0.29	35
0.30	36
0.32	37
0.33	38
0.34	39
0.35	40
0.37	41
0.38	42
0.39	43
0.41	44
0.42	45
0.43	46
0.45	47
0.46	48
0.48	49
0.49	50
0.51	51
0.52	52
0.54	53
0.56	54
0.57	55
0.59	56
0.61	57
0.63	58
0.65	59
0.67	60
0.69	61
0.71	62
0.73	63
0.75	64
0.78	65
0.81	66
0.84	67
0.87	68
0.89	69
0.93	70
0.96	71
1.00	72
1.03	73
1.07	74
1.10	75
1.14	76
1.18	77
1.22	78
1.27	79
1.32	80
1.38	81
1.43	82
1.50	83
1.56	84
1.62	85
1.69	86
1.77	87
1.86	88
1.94	89
2.04	90
2.14	91
2.27	92
2.41	93
2.58	94
2.78	95
3.01	96
3.35	97
3.78	98
4.54	99
8.90	100