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
0.12	2
0.15	3
0.19	4
0.23	5
0.26	6
0.29	7
0.33	8
0.37	9
0.40	10
0.45	11
0.49	12
0.53	13
0.57	14
0.61	15
0.65	16
0.69	17
0.74	18
0.78	19
0.82	20
0.87	21
0.91	22
0.95	23
1.00	24
1.05	25
1.09	26
1.14	27
1.18	28
1.24	29
1.29	30
1.34	31
1.40	32
1.44	33
1.50	34
1.56	35
1.63	36
1.71	37
1.79	38
1.86	39
1.93	40
2.00	41
2.07	42
2.15	43
2.24	44
2.31	45
2.40	46
2.50	47
2.62	48
2.72	49
2.82	50
2.92	51
3.04	52
3.20	53
3.33	54
3.48	55
3.62	56
3.75	57
3.90	58
4.05	59
4.20	60
4.36	61
4.50	62
4.68	63
4.86	64
5.03	65
5.27	66
5.48	67
5.70	68
6.00	69
6.24	70
6.51	71
6.80	72
7.07	73
7.37	74
7.67	75
8.00	76
8.33	77
8.77	78
9.25	79
9.68	80
10.12	81
10.70	82
11.38	83
12.01	84
12.80	85
13.50	86
14.37	87
15.01	88
16.04	89
17.17	90
18.63	91
20.01	92
22.01	93
24.06	94
27.19	95
31.05	96
37.08	97
44.14	98
56.98	99
116.00	100