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
0.18	1
0.32	2
0.45	3
0.57	4
0.69	5
0.78	6
0.88	7
0.96	8
1.05	9
1.13	10
1.20	11
1.27	12
1.35	13
1.42	14
1.50	15
1.57	16
1.63	17
1.69	18
1.76	19
1.83	20
1.89	21
1.95	22
2.01	23
2.07	24
2.13	25
2.19	26
2.24	27
2.31	28
2.38	29
2.44	30
2.50	31
2.56	32
2.62	33
2.68	34
2.75	35
2.81	36
2.88	37
2.94	38
3.00	39
3.07	40
3.13	41
3.19	42
3.25	43
3.31	44
3.38	45
3.43	46
3.51	47
3.58	48
3.65	49
3.72	50
3.80	51
3.86	52
3.93	53
4.00	54
4.07	55
4.15	56
4.22	57
4.31	58
4.38	59
4.47	60
4.55	61
4.64	62
4.71	63
4.80	64
4.90	65
4.97	66
5.07	67
5.15	68
5.24	69
5.33	70
5.42	71
5.52	72
5.62	73
5.73	74
5.84	75
5.95	76
6.07	77
6.20	78
6.34	79
6.46	80
6.61	81
6.78	82
6.96	83
7.12	84
7.28	85
7.49	86
7.71	87
7.93	88
8.21	89
8.44	90
8.71	91
9.05	92
9.40	93
9.77	94
10.29	95
10.92	96
11.65	97
12.72	98
14.36	99
24.72	100