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
0.05	9
0.06	10
0.07	11
0.08	12
0.08	13
0.09	14
0.10	15
0.11	16
0.11	17
0.12	18
0.13	19
0.14	20
0.15	21
0.16	22
0.17	23
0.18	24
0.19	25
0.20	26
0.21	27
0.22	28
0.23	29
0.24	30
0.25	31
0.26	32
0.27	33
0.28	34
0.29	35
0.31	36
0.32	37
0.33	38
0.34	39
0.35	40
0.36	41
0.38	42
0.39	43
0.40	44
0.41	45
0.43	46
0.44	47
0.46	48
0.47	49
0.49	50
0.50	51
0.52	52
0.54	53
0.55	54
0.57	55
0.59	56
0.61	57
0.63	58
0.65	59
0.67	60
0.69	61
0.72	62
0.74	63
0.76	64
0.79	65
0.81	66
0.84	67
0.87	68
0.90	69
0.93	70
0.96	71
1.00	72
1.04	73
1.07	74
1.11	75
1.15	76
1.20	77
1.25	78
1.30	79
1.35	80
1.40	81
1.45	82
1.52	83
1.58	84
1.66	85
1.74	86
1.83	87
1.92	88
2.01	89
2.11	90
2.23	91
2.37	92
2.52	93
2.74	94
2.95	95
3.25	96
3.68	97
4.19	98
5.08	99
9.79	100