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
0.21	1
0.34	2
0.46	3
0.59	4
0.70	5
0.80	6
0.90	7
1.01	8
1.11	9
1.20	10
1.30	11
1.39	12
1.47	13
1.56	14
1.64	15
1.73	16
1.81	17
1.89	18
2.00	19
2.08	20
2.16	21
2.24	22
2.32	23
2.41	24
2.50	25
2.58	26
2.67	27
2.76	28
2.84	29
2.92	30
3.01	31
3.08	32
3.17	33
3.24	34
3.32	35
3.40	36
3.48	37
3.57	38
3.64	39
3.73	40
3.81	41
3.89	42
3.97	43
4.06	44
4.14	45
4.22	46
4.31	47
4.41	48
4.51	49
4.58	50
4.67	51
4.76	52
4.86	53
4.96	54
5.05	55
5.15	56
5.26	57
5.36	58
5.47	59
5.57	60
5.69	61
5.81	62
5.92	63
6.04	64
6.15	65
6.27	66
6.38	67
6.51	68
6.65	69
6.78	70
6.91	71
7.05	72
7.19	73
7.35	74
7.51	75
7.65	76
7.81	77
7.97	78
8.15	79
8.33	80
8.50	81
8.69	82
8.89	83
9.10	84
9.32	85
9.57	86
9.84	87
10.13	88
10.44	89
10.77	90
11.15	91
11.54	92
11.97	93
12.45	94
13.01	95
13.70	96
14.58	97
15.83	98
17.73	99
29.35	100