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
0.09	1
0.25	2
0.39	3
0.54	4
0.70	5
0.77	6
0.86	7
0.91	8
0.97	9
1.04	10
1.10	11
1.15	12
1.21	13
1.28	14
1.33	15
1.37	16
1.41	17
1.45	18
1.50	19
1.54	20
1.60	21
1.64	22
1.69	23
1.75	24
1.79	25
1.84	26
1.89	27
1.96	28
1.99	29
2.04	30
2.09	31
2.13	32
2.18	33
2.22	34
2.27	35
2.31	36
2.35	37
2.40	38
2.44	39
2.49	40
2.54	41
2.58	42
2.63	43
2.67	44
2.70	45
2.75	46
2.81	47
2.85	48
2.90	49
2.95	50
3.01	51
3.05	52
3.10	53
3.15	54
3.18	55
3.22	56
3.28	57
3.34	58
3.40	59
3.46	60
3.51	61
3.56	62
3.62	63
3.68	64
3.74	65
3.80	66
3.86	67
3.92	68
3.97	69
4.02	70
4.10	71
4.16	72
4.21	73
4.28	74
4.38	75
4.43	76
4.48	77
4.58	78
4.66	79
4.75	80
4.82	81
4.91	82
5.04	83
5.14	84
5.26	85
5.37	86
5.49	87
5.68	88
5.81	89
6.05	90
6.33	91
6.59	92
6.91	93
7.26	94
7.58	95
7.85	96
8.44	97
9.32	98
11.33	99
20.85	100