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
0.17	1
0.29	2
0.41	3
0.52	4
0.61	5
0.70	6
0.79	7
0.86	8
0.94	9
1.01	10
1.09	11
1.16	12
1.23	13
1.29	14
1.35	15
1.41	16
1.48	17
1.53	18
1.59	19
1.67	20
1.72	21
1.79	22
1.85	23
1.91	24
1.97	25
2.03	26
2.09	27
2.15	28
2.20	29
2.26	30
2.32	31
2.37	32
2.43	33
2.49	34
2.55	35
2.61	36
2.67	37
2.73	38
2.80	39
2.87	40
2.93	41
2.99	42
3.06	43
3.12	44
3.18	45
3.25	46
3.31	47
3.38	48
3.44	49
3.50	50
3.56	51
3.63	52
3.68	53
3.76	54
3.83	55
3.90	56
3.97	57
4.05	58
4.12	59
4.19	60
4.27	61
4.35	62
4.44	63
4.51	64
4.58	65
4.67	66
4.77	67
4.86	68
4.95	69
5.05	70
5.14	71
5.24	72
5.34	73
5.44	74
5.56	75
5.67	76
5.78	77
5.90	78
6.03	79
6.16	80
6.30	81
6.45	82
6.59	83
6.72	84
6.91	85
7.08	86
7.27	87
7.49	88
7.69	89
7.90	90
8.17	91
8.46	92
8.82	93
9.19	94
9.60	95
10.08	96
10.71	97
11.62	98
13.10	99
27.90	100