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
0.20	1
0.32	2
0.44	3
0.57	4
0.68	5
0.79	6
0.88	7
0.97	8
1.05	9
1.13	10
1.21	11
1.28	12
1.35	13
1.42	14
1.49	15
1.56	16
1.62	17
1.69	18
1.76	19
1.82	20
1.88	21
1.95	22
2.01	23
2.07	24
2.12	25
2.18	26
2.24	27
2.29	28
2.36	29
2.41	30
2.47	31
2.54	32
2.60	33
2.66	34
2.72	35
2.79	36
2.85	37
2.92	38
2.98	39
3.04	40
3.10	41
3.16	42
3.23	43
3.28	44
3.36	45
3.43	46
3.49	47
3.56	48
3.62	49
3.69	50
3.77	51
3.83	52
3.90	53
3.97	54
4.03	55
4.11	56
4.18	57
4.26	58
4.34	59
4.41	60
4.50	61
4.58	62
4.65	63
4.73	64
4.82	65
4.91	66
5.00	67
5.09	68
5.20	69
5.30	70
5.39	71
5.49	72
5.59	73
5.70	74
5.81	75
5.91	76
6.02	77
6.14	78
6.26	79
6.41	80
6.57	81
6.71	82
6.86	83
7.05	84
7.25	85
7.46	86
7.68	87
7.87	88
8.07	89
8.32	90
8.53	91
8.80	92
9.19	93
9.58	94
10.12	95
10.80	96
11.55	97
12.57	98
14.31	99
26.92	100