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
0.10	2
0.11	3
0.13	4
0.15	5
0.16	6
0.17	7
0.19	8
0.20	9
0.22	10
0.25	11
0.26	12
0.27	13
0.29	14
0.32	15
0.34	16
0.34	17
0.38	18
0.40	19
0.43	20
0.45	21
0.50	22
0.51	23
0.55	24
0.59	25
0.62	26
0.65	27
0.68	28
0.72	29
0.76	30
0.78	31
0.83	32
0.88	33
0.89	34
1.00	35
1.01	36
1.03	37
1.04	38
1.11	39
1.15	40
1.17	41
1.21	42
1.26	43
1.29	44
1.34	45
1.40	46
1.41	47
1.45	48
1.51	49
1.56	50
1.60	51
1.67	52
1.71	53
1.75	54
1.76	55
1.80	56
1.88	57
1.93	58
2.01	59
2.03	60
2.10	61
2.15	62
2.23	63
2.29	64
2.34	65
2.34	66
2.38	67
2.48	68
2.56	69
2.63	70
2.68	71
2.78	72
2.83	73
3.00	74
3.02	75
3.04	76
3.20	77
3.31	78
3.43	79
3.51	80
3.57	81
3.73	82
3.86	83
4.02	84
4.17	85
4.29	86
4.51	87
4.67	88
4.82	89
5.04	90
5.27	91
5.53	92
5.81	93
6.15	94
6.60	95
7.03	96
7.67	97
8.62	98
10.41	99
25.18	100