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
0.37	1
0.49	2
0.57	3
0.64	4
0.70	5
0.76	6
0.85	7
0.92	8
0.96	9
0.99	10
1.09	11
1.16	12
1.20	13
1.22	14
1.28	15
1.32	16
1.37	17
1.43	18
1.47	19
1.52	20
1.54	21
1.60	22
1.65	23
1.69	24
1.74	25
1.78	26
1.82	27
1.85	28
1.89	29
1.94	30
1.96	31
2.00	32
2.03	33
2.07	34
2.10	35
2.15	36
2.19	37
2.23	38
2.26	39
2.33	40
2.38	41
2.41	42
2.45	43
2.48	44
2.54	45
2.57	46
2.63	47
2.67	48
2.70	49
2.74	50
2.82	51
2.89	52
2.93	53
2.95	54
2.99	55
3.03	56
3.08	57
3.12	58
3.17	59
3.22	60
3.28	61
3.33	62
3.38	63
3.44	64
3.50	65
3.56	66
3.64	67
3.75	68
3.83	69
3.89	70
3.98	71
4.10	72
4.20	73
4.30	74
4.37	75
4.47	76
4.54	77
4.65	78
4.77	79
4.90	80
5.06	81
5.19	82
5.36	83
5.53	84
5.74	85
6.00	86
6.11	87
6.29	88
6.63	89
6.86	90
7.37	91
7.78	92
8.21	93
8.90	94
9.78	95
10.89	96
12.03	97
15.65	98
28.76	99
690.23	100