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
0.06	1
0.07	2
0.08	3
0.09	4
0.09	5
0.10	6
0.11	7
0.11	8
0.13	9
0.13	10
0.14	11
0.15	12
0.16	13
0.17	14
0.17	15
0.19	16
0.20	17
0.21	18
0.22	19
0.23	20
0.25	21
0.26	22
0.27	23
0.29	24
0.30	25
0.34	26
0.34	27
0.38	28
0.40	29
0.43	30
0.45	31
0.48	32
0.51	33
0.54	34
0.57	35
0.59	36
0.63	37
0.65	38
0.68	39
0.70	40
0.73	41
0.77	42
0.78	43
0.81	44
0.84	45
0.86	46
0.91	47
0.91	48
0.95	49
1.01	50
1.02	51
1.05	52
1.09	53
1.11	54
1.12	55
1.18	56
1.22	57
1.25	58
1.26	59
1.31	60
1.36	61
1.40	62
1.43	63
1.43	64
1.51	65
1.54	66
1.58	67
1.65	68
1.68	69
1.69	70
1.76	71
1.82	72
1.84	73
1.89	74
2.00	75
2.02	76
2.04	77
2.10	78
2.15	79
2.21	80
2.27	81
2.34	82
2.43	83
2.51	84
2.55	85
2.69	86
2.76	87
2.86	88
3.02	89
3.11	90
3.31	91
3.40	92
3.64	93
3.83	94
4.13	95
4.51	96
5.03	97
5.78	98
7.06	99
17.67	100