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
0.20	1
0.35	2
0.51	3
0.64	4
0.76	5
0.88	6
0.99	7
1.08	8
1.18	9
1.26	10
1.36	11
1.44	12
1.52	13
1.59	14
1.67	15
1.75	16
1.82	17
1.89	18
1.96	19
2.04	20
2.12	21
2.19	22
2.26	23
2.33	24
2.41	25
2.48	26
2.55	27
2.61	28
2.68	29
2.76	30
2.83	31
2.90	32
2.96	33
3.03	34
3.10	35
3.17	36
3.25	37
3.32	38
3.39	39
3.46	40
3.53	41
3.61	42
3.68	43
3.75	44
3.83	45
3.91	46
3.99	47
4.07	48
4.15	49
4.22	50
4.29	51
4.36	52
4.44	53
4.52	54
4.61	55
4.69	56
4.77	57
4.85	58
4.94	59
5.02	60
5.11	61
5.21	62
5.30	63
5.39	64
5.49	65
5.59	66
5.69	67
5.79	68
5.90	69
6.01	70
6.11	71
6.21	72
6.34	73
6.49	74
6.62	75
6.74	76
6.89	77
7.03	78
7.17	79
7.34	80
7.47	81
7.62	82
7.80	83
7.96	84
8.17	85
8.36	86
8.58	87
8.82	88
9.05	89
9.31	90
9.63	91
9.92	92
10.33	93
10.79	94
11.29	95
11.95	96
12.66	97
13.72	98
15.43	99
25.12	100