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
0.30	1
0.41	2
0.46	3
0.54	4
0.63	5
0.71	6
0.79	7
0.86	8
0.90	9
0.94	10
0.97	11
1.03	12
1.11	13
1.15	14
1.20	15
1.22	16
1.29	17
1.34	18
1.36	19
1.39	20
1.42	21
1.43	22
1.46	23
1.53	24
1.59	25
1.62	26
1.68	27
1.73	28
1.76	29
1.79	30
1.82	31
1.85	32
1.87	33
1.90	34
1.93	35
1.96	36
1.97	37
2.01	38
2.06	39
2.09	40
2.11	41
2.13	42
2.16	43
2.21	44
2.23	45
2.25	46
2.27	47
2.31	48
2.35	49
2.38	50
2.39	51
2.44	52
2.46	53
2.49	54
2.52	55
2.58	56
2.62	57
2.67	58
2.71	59
2.73	60
2.79	61
2.82	62
2.85	63
2.91	64
2.99	65
3.03	66
3.10	67
3.14	68
3.15	69
3.17	70
3.20	71
3.23	72
3.25	73
3.28	74
3.35	75
3.37	76
3.42	77
3.47	78
3.64	79
3.76	80
3.80	81
3.88	82
3.90	83
3.95	84
4.08	85
4.20	86
4.39	87
4.55	88
4.79	89
4.89	90
5.08	91
5.27	92
5.83	93
5.90	94
6.28	95
7.15	96
7.63	97
8.06	98
8.53	99
9.28	100