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
0.42	3
0.55	4
0.65	5
0.74	6
0.82	7
0.90	8
0.97	9
1.05	10
1.13	11
1.20	12
1.26	13
1.33	14
1.40	15
1.47	16
1.53	17
1.58	18
1.65	19
1.71	20
1.77	21
1.84	22
1.90	23
1.95	24
2.01	25
2.07	26
2.13	27
2.18	28
2.24	29
2.30	30
2.35	31
2.41	32
2.46	33
2.52	34
2.58	35
2.63	36
2.69	37
2.74	38
2.81	39
2.86	40
2.92	41
3.00	42
3.05	43
3.10	44
3.16	45
3.23	46
3.29	47
3.36	48
3.43	49
3.49	50
3.56	51
3.63	52
3.69	53
3.76	54
3.83	55
3.90	56
3.97	57
4.04	58
4.12	59
4.20	60
4.28	61
4.36	62
4.43	63
4.51	64
4.58	65
4.66	66
4.75	67
4.83	68
4.91	69
5.01	70
5.10	71
5.21	72
5.30	73
5.40	74
5.50	75
5.61	76
5.71	77
5.82	78
5.95	79
6.07	80
6.22	81
6.38	82
6.53	83
6.69	84
6.85	85
7.00	86
7.17	87
7.39	88
7.62	89
7.84	90
8.13	91
8.40	92
8.75	93
9.10	94
9.50	95
9.99	96
10.64	97
11.52	98
13.10	99
26.00	100