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
0.11	1
0.27	2
0.39	3
0.58	4
0.70	5
0.75	6
0.87	7
0.94	8
1.00	9
1.04	10
1.10	11
1.15	12
1.20	13
1.26	14
1.31	15
1.35	16
1.41	17
1.45	18
1.50	19
1.56	20
1.59	21
1.65	22
1.69	23
1.74	24
1.79	25
1.83	26
1.87	27
1.91	28
1.96	29
2.00	30
2.06	31
2.10	32
2.15	33
2.20	34
2.24	35
2.27	36
2.32	37
2.36	38
2.42	39
2.45	40
2.50	41
2.54	42
2.57	43
2.60	44
2.64	45
2.68	46
2.74	47
2.78	48
2.82	49
2.90	50
2.95	51
3.01	52
3.04	53
3.09	54
3.16	55
3.21	56
3.26	57
3.30	58
3.34	59
3.40	60
3.44	61
3.49	62
3.55	63
3.60	64
3.68	65
3.72	66
3.79	67
3.84	68
3.91	69
3.97	70
4.04	71
4.09	72
4.15	73
4.23	74
4.31	75
4.39	76
4.45	77
4.55	78
4.64	79
4.74	80
4.85	81
4.94	82
5.04	83
5.18	84
5.29	85
5.40	86
5.52	87
5.68	88
5.88	89
6.03	90
6.26	91
6.55	92
6.80	93
7.14	94
7.40	95
7.78	96
8.15	97
8.88	98
11.10	99
21.56	100