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
0.09	2
0.11	3
0.13	4
0.14	5
0.16	6
0.17	7
0.19	8
0.20	9
0.21	10
0.23	11
0.25	12
0.26	13
0.29	14
0.30	15
0.34	16
0.34	17
0.37	18
0.40	19
0.42	20
0.44	21
0.50	22
0.51	23
0.54	24
0.58	25
0.61	26
0.64	27
0.68	28
0.71	29
0.76	30
0.78	31
0.83	32
0.88	33
0.89	34
0.96	35
1.01	36
1.02	37
1.04	38
1.11	39
1.15	40
1.17	41
1.21	42
1.26	43
1.30	44
1.34	45
1.40	46
1.41	47
1.46	48
1.51	49
1.56	50
1.62	51
1.67	52
1.73	53
1.75	54
1.76	55
1.81	56
1.89	57
1.95	58
2.02	59
2.03	60
2.10	61
2.18	62
2.26	63
2.33	64
2.34	65
2.34	66
2.40	67
2.51	68
2.58	69
2.64	70
2.70	71
2.80	72
2.88	73
3.01	74
3.03	75
3.10	76
3.21	77
3.35	78
3.50	79
3.52	80
3.64	81
3.80	82
4.00	83
4.07	84
4.22	85
4.40	86
4.60	87
4.72	88
5.00	89
5.18	90
5.38	91
5.67	92
6.02	93
6.34	94
6.82	95
7.21	96
7.83	97
8.86	98
10.44	99
27.33	100