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
0.01	1
0.02	2
0.02	3
0.03	4
0.03	5
0.04	6
0.04	7
0.05	8
0.06	9
0.06	10
0.07	11
0.08	12
0.09	13
0.09	14
0.10	15
0.11	16
0.12	17
0.13	18
0.14	19
0.15	20
0.16	21
0.16	22
0.17	23
0.18	24
0.19	25
0.20	26
0.21	27
0.22	28
0.24	29
0.25	30
0.26	31
0.27	32
0.28	33
0.29	34
0.30	35
0.31	36
0.32	37
0.34	38
0.35	39
0.36	40
0.37	41
0.39	42
0.40	43
0.41	44
0.43	45
0.44	46
0.46	47
0.47	48
0.49	49
0.51	50
0.53	51
0.54	52
0.56	53
0.58	54
0.59	55
0.61	56
0.63	57
0.65	58
0.67	59
0.69	60
0.71	61
0.74	62
0.76	63
0.79	64
0.81	65
0.84	66
0.87	67
0.90	68
0.93	69
0.96	70
1.00	71
1.03	72
1.07	73
1.11	74
1.15	75
1.19	76
1.23	77
1.28	78
1.34	79
1.39	80
1.45	81
1.50	82
1.56	83
1.63	84
1.72	85
1.79	86
1.87	87
1.97	88
2.06	89
2.17	90
2.30	91
2.43	92
2.61	93
2.81	94
3.05	95
3.31	96
3.77	97
4.35	98
5.24	99
10.08	100