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
0.08	1
0.10	2
0.11	3
0.13	4
0.15	5
0.17	6
0.17	7
0.20	8
0.20	9
0.22	10
0.25	11
0.26	12
0.27	13
0.29	14
0.32	15
0.34	16
0.34	17
0.38	18
0.40	19
0.43	20
0.46	21
0.50	22
0.51	23
0.55	24
0.59	25
0.63	26
0.67	27
0.69	28
0.72	29
0.76	30
0.80	31
0.84	32
0.88	33
0.90	34
1.00	35
1.01	36
1.02	37
1.05	38
1.11	39
1.17	40
1.17	41
1.22	42
1.26	43
1.29	44
1.35	45
1.40	46
1.41	47
1.46	48
1.51	49
1.56	50
1.61	51
1.67	52
1.72	53
1.75	54
1.76	55
1.81	56
1.88	57
1.94	58
2.02	59
2.03	60
2.10	61
2.16	62
2.25	63
2.31	64
2.34	65
2.34	66
2.40	67
2.50	68
2.57	69
2.63	70
2.68	71
2.78	72
2.82	73
3.00	74
3.02	75
3.04	76
3.18	77
3.30	78
3.43	79
3.51	80
3.57	81
3.72	82
3.86	83
4.02	84
4.15	85
4.27	86
4.46	87
4.67	88
4.80	89
5.02	90
5.26	91
5.51	92
5.76	93
6.10	94
6.58	95
7.03	96
7.63	97
8.60	98
10.19	99
25.18	100