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
0.15	14
0.17	15
0.19	16
0.20	17
0.22	18
0.23	19
0.25	20
0.26	21
0.28	22
0.29	23
0.31	24
0.32	25
0.34	26
0.36	27
0.38	28
0.39	29
0.41	30
0.43	31
0.45	32
0.47	33
0.48	34
0.51	35
0.53	36
0.55	37
0.57	38
0.59	39
0.61	40
0.64	41
0.65	42
0.67	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
0.92	53
0.95	54
0.97	55
1.01	56
1.04	57
1.07	58
1.11	59
1.14	60
1.18	61
1.22	62
1.25	63
1.29	64
1.34	65
1.37	66
1.41	67
1.46	68
1.51	69
1.56	70
1.61	71
1.67	72
1.73	73
1.79	74
1.85	75
1.92	76
2.00	77
2.06	78
2.14	79
2.21	80
2.29	81
2.37	82
2.45	83
2.55	84
2.65	85
2.76	86
2.88	87
3.01	88
3.15	89
3.29	90
3.45	91
3.66	92
3.87	93
4.12	94
4.40	95
4.72	96
5.15	97
5.73	98
6.67	99
11.63	100