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
0.42	3
0.51	4
0.62	5
0.71	6
0.78	7
0.86	8
0.93	9
1.01	10
1.08	11
1.16	12
1.22	13
1.28	14
1.34	15
1.41	16
1.47	17
1.53	18
1.59	19
1.65	20
1.72	21
1.78	22
1.84	23
1.90	24
1.95	25
2.02	26
2.07	27
2.12	28
2.18	29
2.23	30
2.30	31
2.36	32
2.41	33
2.48	34
2.54	35
2.60	36
2.67	37
2.72	38
2.79	39
2.85	40
2.92	41
2.98	42
3.04	43
3.10	44
3.16	45
3.23	46
3.29	47
3.36	48
3.41	49
3.47	50
3.55	51
3.61	52
3.67	53
3.75	54
3.81	55
3.87	56
3.96	57
4.03	58
4.11	59
4.19	60
4.27	61
4.34	62
4.43	63
4.51	64
4.60	65
4.67	66
4.77	67
4.86	68
4.95	69
5.03	70
5.13	71
5.23	72
5.33	73
5.43	74
5.55	75
5.65	76
5.75	77
5.87	78
5.98	79
6.12	80
6.28	81
6.41	82
6.55	83
6.70	84
6.87	85
7.03	86
7.22	87
7.42	88
7.65	89
7.87	90
8.14	91
8.47	92
8.79	93
9.16	94
9.64	95
10.10	96
10.69	97
11.62	98
13.18	99
27.94	100