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
0.36	1
0.46	2
0.56	3
0.62	4
0.71	5
0.79	6
0.89	7
0.94	8
1.00	9
1.05	10
1.11	11
1.17	12
1.21	13
1.26	14
1.29	15
1.33	16
1.37	17
1.42	18
1.47	19
1.50	20
1.54	21
1.58	22
1.61	23
1.68	24
1.72	25
1.77	26
1.81	27
1.85	28
1.89	29
1.95	30
2.00	31
2.04	32
2.09	33
2.15	34
2.18	35
2.23	36
2.28	37
2.33	38
2.37	39
2.43	40
2.49	41
2.53	42
2.57	43
2.60	44
2.64	45
2.67	46
2.72	47
2.76	48
2.81	49
2.85	50
2.89	51
2.94	52
2.97	53
3.00	54
3.04	55
3.08	56
3.12	57
3.15	58
3.20	59
3.30	60
3.35	61
3.40	62
3.45	63
3.51	64
3.61	65
3.70	66
3.75	67
3.81	68
3.93	69
3.99	70
4.10	71
4.22	72
4.33	73
4.39	74
4.50	75
4.56	76
4.69	77
4.81	78
4.99	79
5.14	80
5.28	81
5.44	82
5.61	83
5.79	84
6.00	85
6.25	86
6.42	87
6.82	88
7.12	89
7.62	90
7.93	91
8.58	92
9.22	93
9.77	94
10.95	95
11.96	96
14.03	97
17.25	98
23.70	99
247.50	100