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
0.11	2
0.15	3
0.19	4
0.22	5
0.26	6
0.30	7
0.33	8
0.37	9
0.40	10
0.44	11
0.48	12
0.52	13
0.57	14
0.61	15
0.66	16
0.69	17
0.73	18
0.78	19
0.82	20
0.86	21
0.90	22
0.94	23
1.00	24
1.04	25
1.08	26
1.14	27
1.20	28
1.25	29
1.30	30
1.35	31
1.41	32
1.48	33
1.53	34
1.58	35
1.65	36
1.71	37
1.79	38
1.86	39
1.93	40
2.00	41
2.08	42
2.15	43
2.21	44
2.29	45
2.40	46
2.50	47
2.58	48
2.68	49
2.80	50
2.90	51
3.00	52
3.11	53
3.20	54
3.34	55
3.45	56
3.60	57
3.73	58
3.89	59
4.00	60
4.17	61
4.33	62
4.49	63
4.67	64
4.81	65
5.00	66
5.27	67
5.50	68
5.75	69
6.00	70
6.31	71
6.54	72
6.80	73
7.09	74
7.34	75
7.67	76
8.00	77
8.34	78
8.67	79
9.06	80
9.59	81
10.01	82
10.50	83
11.16	84
11.71	85
12.45	86
13.05	87
13.84	88
14.98	89
16.00	90
17.08	91
18.52	92
20.05	93
22.17	94
24.74	95
28.03	96
33.40	97
40.40	98
52.05	99
146.00	100