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
0.07	1
0.10	2
0.13	3
0.15	4
0.18	5
0.22	6
0.24	7
0.27	8
0.30	9
0.33	10
0.36	11
0.39	12
0.43	13
0.46	14
0.49	15
0.53	16
0.57	17
0.61	18
0.64	19
0.67	20
0.71	21
0.73	22
0.76	23
0.80	24
0.83	25
0.88	26
0.91	27
0.96	28
1.00	29
1.04	30
1.08	31
1.13	32
1.17	33
1.22	34
1.26	35
1.32	36
1.36	37
1.41	38
1.46	39
1.52	40
1.61	41
1.66	42
1.71	43
1.79	44
1.85	45
1.92	46
1.99	47
2.06	48
2.16	49
2.26	50
2.33	51
2.42	52
2.50	53
2.60	54
2.70	55
2.80	56
2.92	57
3.06	58
3.20	59
3.35	60
3.49	61
3.63	62
3.75	63
3.91	64
4.06	65
4.23	66
4.39	67
4.56	68
4.79	69
5.01	70
5.21	71
5.47	72
5.71	73
6.00	74
6.27	75
6.61	76
6.90	77
7.25	78
7.80	79
8.14	80
8.47	81
8.92	82
9.39	83
10.08	84
10.83	85
11.39	86
11.98	87
12.79	88
13.97	89
15.01	90
16.67	91
18.17	92
20.70	93
23.59	94
25.73	95
30.02	96
34.58	97
45.41	98
60.92	99
186.00	100