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
0.12	2
0.15	3
0.19	4
0.22	5
0.26	6
0.29	7
0.33	8
0.37	9
0.40	10
0.45	11
0.50	12
0.54	13
0.58	14
0.62	15
0.66	16
0.71	17
0.75	18
0.79	19
0.84	20
0.88	21
0.92	22
0.97	23
1.01	24
1.06	25
1.11	26
1.16	27
1.21	28
1.27	29
1.31	30
1.35	31
1.40	32
1.46	33
1.52	34
1.58	35
1.65	36
1.72	37
1.79	38
1.86	39
1.94	40
2.00	41
2.09	42
2.18	43
2.27	44
2.34	45
2.43	46
2.53	47
2.67	48
2.77	49
2.86	50
2.97	51
3.10	52
3.25	53
3.39	54
3.53	55
3.70	56
3.84	57
4.00	58
4.18	59
4.34	60
4.50	61
4.64	62
4.82	63
5.00	64
5.17	65
5.38	66
5.60	67
5.83	68
6.12	69
6.37	70
6.68	71
7.00	72
7.25	73
7.50	74
7.91	75
8.20	76
8.60	77
9.01	78
9.53	79
10.00	80
10.34	81
11.00	82
11.68	83
12.36	84
13.01	85
13.78	86
14.74	87
15.41	88
16.54	89
17.60	90
19.09	91
20.60	92
22.64	93
25.16	94
28.58	95
33.00	96
38.58	97
44.95	98
58.05	99
144.00	100