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
0.10	1
0.26	2
0.43	3
0.56	4
0.69	5
0.79	6
0.87	7
0.95	8
1.02	9
1.09	10
1.16	11
1.22	12
1.29	13
1.33	14
1.37	15
1.43	16
1.48	17
1.55	18
1.58	19
1.64	20
1.69	21
1.74	22
1.80	23
1.84	24
1.89	25
1.94	26
1.99	27
2.03	28
2.09	29
2.15	30
2.20	31
2.24	32
2.28	33
2.34	34
2.38	35
2.42	36
2.45	37
2.50	38
2.54	39
2.60	40
2.66	41
2.70	42
2.75	43
2.80	44
2.87	45
2.93	46
2.99	47
3.03	48
3.09	49
3.13	50
3.18	51
3.24	52
3.31	53
3.35	54
3.39	55
3.46	56
3.52	57
3.59	58
3.67	59
3.72	60
3.77	61
3.83	62
3.88	63
3.92	64
3.99	65
4.08	66
4.16	67
4.21	68
4.27	69
4.33	70
4.41	71
4.48	72
4.56	73
4.62	74
4.70	75
4.77	76
4.84	77
4.91	78
5.01	79
5.16	80
5.28	81
5.40	82
5.49	83
5.61	84
5.75	85
5.87	86
6.02	87
6.17	88
6.31	89
6.50	90
6.63	91
6.87	92
7.06	93
7.35	94
7.68	95
8.22	96
8.73	97
9.49	98
11.13	99
18.14	100