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
0.16	1
0.31	2
0.43	3
0.56	4
0.66	5
0.77	6
0.87	7
0.97	8
1.05	9
1.13	10
1.22	11
1.28	12
1.36	13
1.43	14
1.50	15
1.57	16
1.63	17
1.70	18
1.77	19
1.84	20
1.91	21
1.97	22
2.04	23
2.11	24
2.19	25
2.24	26
2.31	27
2.38	28
2.45	29
2.51	30
2.57	31
2.62	32
2.69	33
2.76	34
2.82	35
2.88	36
2.95	37
3.02	38
3.10	39
3.16	40
3.23	41
3.29	42
3.36	43
3.43	44
3.50	45
3.58	46
3.65	47
3.73	48
3.81	49
3.88	50
3.96	51
4.03	52
4.11	53
4.20	54
4.27	55
4.33	56
4.41	57
4.49	58
4.58	59
4.68	60
4.76	61
4.85	62
4.93	63
5.02	64
5.11	65
5.20	66
5.29	67
5.38	68
5.47	69
5.57	70
5.67	71
5.77	72
5.88	73
5.98	74
6.11	75
6.23	76
6.35	77
6.47	78
6.62	79
6.77	80
6.91	81
7.06	82
7.21	83
7.39	84
7.57	85
7.78	86
7.98	87
8.19	88
8.45	89
8.67	90
8.97	91
9.31	92
9.67	93
10.13	94
10.66	95
11.23	96
12.02	97
13.13	98
14.75	99
28.06	100