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
0.16	1
0.29	2
0.44	3
0.55	4
0.67	5
0.77	6
0.87	7
0.95	8
1.05	9
1.13	10
1.20	11
1.27	12
1.34	13
1.41	14
1.48	15
1.55	16
1.62	17
1.69	18
1.76	19
1.83	20
1.90	21
1.96	22
2.03	23
2.10	24
2.16	25
2.23	26
2.29	27
2.36	28
2.42	29
2.49	30
2.55	31
2.60	32
2.67	33
2.74	34
2.81	35
2.87	36
2.93	37
3.00	38
3.06	39
3.13	40
3.20	41
3.27	42
3.33	43
3.40	44
3.47	45
3.54	46
3.61	47
3.69	48
3.76	49
3.83	50
3.90	51
3.97	52
4.05	53
4.12	54
4.19	55
4.27	56
4.35	57
4.42	58
4.50	59
4.58	60
4.67	61
4.76	62
4.86	63
4.95	64
5.04	65
5.12	66
5.21	67
5.30	68
5.40	69
5.49	70
5.59	71
5.70	72
5.81	73
5.93	74
6.03	75
6.16	76
6.28	77
6.39	78
6.51	79
6.66	80
6.81	81
6.98	82
7.13	83
7.32	84
7.51	85
7.70	86
7.91	87
8.11	88
8.36	89
8.61	90
8.92	91
9.22	92
9.54	93
9.96	94
10.50	95
11.20	96
11.97	97
13.15	98
14.80	99
28.33	100