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
0.34	2
0.47	3
0.61	4
0.73	5
0.85	6
0.96	7
1.06	8
1.15	9
1.23	10
1.32	11
1.40	12
1.48	13
1.55	14
1.63	15
1.70	16
1.79	17
1.86	18
1.93	19
2.01	20
2.08	21
2.15	22
2.22	23
2.30	24
2.37	25
2.44	26
2.50	27
2.58	28
2.65	29
2.72	30
2.79	31
2.87	32
2.93	33
3.00	34
3.07	35
3.14	36
3.21	37
3.28	38
3.36	39
3.42	40
3.49	41
3.57	42
3.64	43
3.72	44
3.79	45
3.87	46
3.95	47
4.02	48
4.09	49
4.17	50
4.25	51
4.33	52
4.41	53
4.49	54
4.57	55
4.65	56
4.73	57
4.81	58
4.90	59
4.99	60
5.07	61
5.17	62
5.26	63
5.35	64
5.44	65
5.55	66
5.66	67
5.77	68
5.87	69
5.97	70
6.08	71
6.19	72
6.31	73
6.42	74
6.56	75
6.69	76
6.84	77
6.97	78
7.10	79
7.27	80
7.41	81
7.59	82
7.76	83
7.94	84
8.15	85
8.37	86
8.57	87
8.77	88
9.00	89
9.26	90
9.57	91
9.88	92
10.25	93
10.65	94
11.22	95
11.76	96
12.47	97
13.70	98
15.57	99
25.64	100