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
0.17	1
0.31	2
0.43	3
0.57	4
0.67	5
0.78	6
0.87	7
0.96	8
1.04	9
1.12	10
1.20	11
1.27	12
1.33	13
1.41	14
1.48	15
1.55	16
1.62	17
1.70	18
1.77	19
1.83	20
1.89	21
1.96	22
2.02	23
2.09	24
2.16	25
2.22	26
2.28	27
2.34	28
2.41	29
2.47	30
2.53	31
2.59	32
2.65	33
2.72	34
2.79	35
2.85	36
2.91	37
2.97	38
3.03	39
3.09	40
3.15	41
3.23	42
3.29	43
3.35	44
3.42	45
3.50	46
3.57	47
3.64	48
3.70	49
3.78	50
3.84	51
3.91	52
3.98	53
4.06	54
4.13	55
4.20	56
4.28	57
4.36	58
4.45	59
4.53	60
4.61	61
4.69	62
4.78	63
4.87	64
4.95	65
5.04	66
5.14	67
5.22	68
5.32	69
5.41	70
5.52	71
5.63	72
5.73	73
5.85	74
5.96	75
6.07	76
6.21	77
6.34	78
6.48	79
6.61	80
6.74	81
6.89	82
7.07	83
7.25	84
7.46	85
7.66	86
7.87	87
8.05	88
8.28	89
8.50	90
8.80	91
9.09	92
9.46	93
9.86	94
10.34	95
10.91	96
11.64	97
12.83	98
14.42	99
27.78	100