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
0.30	2
0.43	3
0.57	4
0.68	5
0.77	6
0.87	7
0.96	8
1.03	9
1.11	10
1.17	11
1.24	12
1.32	13
1.39	14
1.46	15
1.53	16
1.59	17
1.65	18
1.71	19
1.78	20
1.84	21
1.90	22
1.95	23
2.02	24
2.08	25
2.14	26
2.20	27
2.26	28
2.32	29
2.37	30
2.43	31
2.49	32
2.55	33
2.62	34
2.67	35
2.73	36
2.80	37
2.86	38
2.92	39
2.99	40
3.06	41
3.13	42
3.20	43
3.27	44
3.34	45
3.39	46
3.46	47
3.52	48
3.59	49
3.66	50
3.71	51
3.78	52
3.85	53
3.92	54
4.00	55
4.07	56
4.14	57
4.20	58
4.28	59
4.36	60
4.44	61
4.52	62
4.61	63
4.69	64
4.79	65
4.86	66
4.94	67
5.03	68
5.12	69
5.22	70
5.31	71
5.40	72
5.50	73
5.61	74
5.72	75
5.84	76
5.96	77
6.09	78
6.22	79
6.35	80
6.49	81
6.64	82
6.80	83
6.97	84
7.16	85
7.34	86
7.55	87
7.77	88
8.01	89
8.24	90
8.50	91
8.83	92
9.16	93
9.57	94
10.06	95
10.56	96
11.28	97
12.34	98
14.03	99
25.11	100