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
0.09	1
0.11	2
0.13	3
0.15	4
0.17	5
0.19	6
0.21	7
0.23	8
0.25	9
0.26	10
0.29	11
0.33	12
0.34	13
0.36	14
0.39	15
0.42	16
0.46	17
0.51	18
0.52	19
0.56	20
0.60	21
0.64	22
0.68	23
0.71	24
0.75	25
0.78	26
0.83	27
0.88	28
0.90	29
0.94	30
1.01	31
1.02	32
1.04	33
1.10	34
1.14	35
1.17	36
1.20	37
1.25	38
1.28	39
1.33	40
1.38	41
1.40	42
1.43	43
1.50	44
1.52	45
1.56	46
1.62	47
1.67	48
1.69	49
1.75	50
1.76	51
1.80	52
1.86	53
1.91	54
2.01	55
2.02	56
2.04	57
2.11	58
2.18	59
2.25	60
2.30	61
2.34	62
2.34	63
2.40	64
2.47	65
2.52	66
2.61	67
2.67	68
2.72	69
2.80	70
2.86	71
3.01	72
3.02	73
3.04	74
3.17	75
3.29	76
3.38	77
3.50	78
3.52	79
3.62	80
3.76	81
3.88	82
4.02	83
4.16	84
4.28	85
4.43	86
4.58	87
4.69	88
4.89	89
5.12	90
5.31	91
5.56	92
5.81	93
6.13	94
6.52	95
7.01	96
7.44	97
8.20	98
9.58	99
20.40	100