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
0.44	3
0.56	4
0.66	5
0.76	6
0.85	7
0.94	8
1.03	9
1.11	10
1.19	11
1.27	12
1.35	13
1.43	14
1.48	15
1.55	16
1.61	17
1.68	18
1.75	19
1.82	20
1.89	21
1.96	22
2.02	23
2.08	24
2.15	25
2.22	26
2.28	27
2.34	28
2.40	29
2.47	30
2.53	31
2.59	32
2.65	33
2.71	34
2.78	35
2.85	36
2.91	37
2.97	38
3.04	39
3.11	40
3.17	41
3.24	42
3.31	43
3.37	44
3.44	45
3.51	46
3.57	47
3.64	48
3.70	49
3.78	50
3.84	51
3.91	52
3.99	53
4.06	54
4.15	55
4.23	56
4.30	57
4.38	58
4.46	59
4.54	60
4.63	61
4.71	62
4.81	63
4.89	64
4.98	65
5.06	66
5.14	67
5.23	68
5.34	69
5.43	70
5.54	71
5.65	72
5.76	73
5.87	74
6.00	75
6.11	76
6.24	77
6.36	78
6.48	79
6.63	80
6.77	81
6.92	82
7.08	83
7.26	84
7.46	85
7.63	86
7.82	87
8.07	88
8.30	89
8.58	90
8.85	91
9.16	92
9.53	93
9.96	94
10.45	95
10.99	96
11.86	97
12.92	98
14.63	99
28.44	100