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
0.36	1
0.45	2
0.55	3
0.61	4
0.69	5
0.79	6
0.87	7
0.95	8
1.00	9
1.06	10
1.12	11
1.18	12
1.23	13
1.28	14
1.33	15
1.37	16
1.41	17
1.46	18
1.50	19
1.55	20
1.59	21
1.63	22
1.67	23
1.70	24
1.74	25
1.77	26
1.82	27
1.87	28
1.90	29
1.96	30
2.01	31
2.04	32
2.08	33
2.15	34
2.20	35
2.24	36
2.26	37
2.30	38
2.37	39
2.41	40
2.47	41
2.52	42
2.55	43
2.58	44
2.62	45
2.66	46
2.69	47
2.74	48
2.79	49
2.83	50
2.87	51
2.91	52
2.96	53
3.02	54
3.08	55
3.12	56
3.17	57
3.21	58
3.27	59
3.34	60
3.40	61
3.46	62
3.51	63
3.57	64
3.63	65
3.70	66
3.77	67
3.87	68
3.94	69
4.02	70
4.11	71
4.18	72
4.27	73
4.33	74
4.46	75
4.62	76
4.78	77
4.85	78
4.95	79
5.14	80
5.35	81
5.49	82
5.63	83
5.77	84
5.97	85
6.17	86
6.40	87
6.64	88
7.04	89
7.52	90
8.03	91
8.57	92
9.27	93
9.83	94
10.78	95
11.89	96
13.68	97
16.48	98
24.96	99
131.00	100