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
0.19	1
0.35	2
0.49	3
0.62	4
0.74	5
0.85	6
0.94	7
1.03	8
1.11	9
1.19	10
1.27	11
1.35	12
1.43	13
1.50	14
1.57	15
1.65	16
1.72	17
1.80	18
1.87	19
1.93	20
2.00	21
2.07	22
2.14	23
2.20	24
2.27	25
2.35	26
2.41	27
2.48	28
2.56	29
2.63	30
2.70	31
2.77	32
2.85	33
2.90	34
2.97	35
3.04	36
3.12	37
3.19	38
3.26	39
3.33	40
3.41	41
3.47	42
3.54	43
3.61	44
3.68	45
3.75	46
3.82	47
3.89	48
3.96	49
4.03	50
4.10	51
4.18	52
4.25	53
4.33	54
4.40	55
4.48	56
4.55	57
4.64	58
4.72	59
4.80	60
4.90	61
5.00	62
5.08	63
5.18	64
5.27	65
5.37	66
5.46	67
5.56	68
5.67	69
5.78	70
5.88	71
6.00	72
6.11	73
6.24	74
6.38	75
6.50	76
6.65	77
6.79	78
6.93	79
7.09	80
7.22	81
7.40	82
7.59	83
7.76	84
7.94	85
8.12	86
8.34	87
8.58	88
8.84	89
9.09	90
9.34	91
9.66	92
10.08	93
10.54	94
11.02	95
11.64	96
12.31	97
13.62	98
15.21	99
25.53	100