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
0.36	2
0.50	3
0.64	4
0.77	5
0.88	6
0.99	7
1.08	8
1.17	9
1.26	10
1.35	11
1.43	12
1.51	13
1.59	14
1.67	15
1.75	16
1.82	17
1.89	18
1.97	19
2.05	20
2.12	21
2.18	22
2.26	23
2.33	24
2.41	25
2.48	26
2.55	27
2.62	28
2.68	29
2.76	30
2.83	31
2.90	32
2.97	33
3.04	34
3.11	35
3.17	36
3.24	37
3.31	38
3.38	39
3.45	40
3.52	41
3.59	42
3.67	43
3.75	44
3.84	45
3.92	46
4.00	47
4.08	48
4.15	49
4.22	50
4.30	51
4.38	52
4.46	53
4.54	54
4.63	55
4.70	56
4.79	57
4.88	58
4.96	59
5.05	60
5.14	61
5.23	62
5.31	63
5.41	64
5.51	65
5.61	66
5.72	67
5.81	68
5.91	69
6.02	70
6.13	71
6.26	72
6.38	73
6.50	74
6.63	75
6.77	76
6.91	77
7.04	78
7.19	79
7.35	80
7.52	81
7.69	82
7.87	83
8.04	84
8.23	85
8.43	86
8.65	87
8.86	88
9.10	89
9.38	90
9.67	91
10.02	92
10.42	93
10.83	94
11.33	95
11.92	96
12.75	97
13.85	98
15.53	99
24.86	100