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
0.02	1
0.02	2
0.03	3
0.03	4
0.04	5
0.04	6
0.05	7
0.06	8
0.06	9
0.07	10
0.08	11
0.08	12
0.09	13
0.10	14
0.11	15
0.12	16
0.13	17
0.13	18
0.14	19
0.15	20
0.16	21
0.17	22
0.18	23
0.18	24
0.20	25
0.20	26
0.21	27
0.22	28
0.23	29
0.24	30
0.26	31
0.27	32
0.28	33
0.29	34
0.30	35
0.31	36
0.33	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
0.45	47
0.47	48
0.48	49
0.50	50
0.51	51
0.53	52
0.55	53
0.57	54
0.59	55
0.60	56
0.62	57
0.64	58
0.66	59
0.68	60
0.70	61
0.73	62
0.75	63
0.77	64
0.80	65
0.83	66
0.85	67
0.88	68
0.91	69
0.93	70
0.96	71
1.00	72
1.03	73
1.07	74
1.11	75
1.16	76
1.20	77
1.25	78
1.29	79
1.34	80
1.40	81
1.44	82
1.50	83
1.56	84
1.62	85
1.70	86
1.78	87
1.86	88
1.95	89
2.05	90
2.15	91
2.29	92
2.43	93
2.60	94
2.79	95
3.04	96
3.37	97
3.79	98
4.52	99
8.87	100