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
0.19	1
0.33	2
0.45	3
0.56	4
0.67	5
0.76	6
0.86	7
0.95	8
1.04	9
1.14	10
1.23	11
1.31	12
1.41	13
1.51	14
1.58	15
1.67	16
1.75	17
1.82	18
1.90	19
2.00	20
2.06	21
2.14	22
2.23	23
2.31	24
2.40	25
2.47	26
2.55	27
2.63	28
2.71	29
2.80	30
2.88	31
2.96	32
3.04	33
3.12	34
3.21	35
3.28	36
3.35	37
3.43	38
3.52	39
3.60	40
3.67	41
3.76	42
3.84	43
3.91	44
4.01	45
4.06	46
4.15	47
4.24	48
4.32	49
4.42	50
4.50	51
4.58	52
4.67	53
4.75	54
4.84	55
4.94	56
5.04	57
5.15	58
5.26	59
5.35	60
5.47	61
5.57	62
5.69	63
5.79	64
5.91	65
6.02	66
6.13	67
6.25	68
6.37	69
6.51	70
6.63	71
6.77	72
6.88	73
7.03	74
7.16	75
7.31	76
7.45	77
7.64	78
7.84	79
8.02	80
8.19	81
8.38	82
8.57	83
8.76	84
8.97	85
9.20	86
9.45	87
9.69	88
9.96	89
10.27	90
10.66	91
11.05	92
11.50	93
11.98	94
12.55	95
13.15	96
14.06	97
15.41	98
17.78	99
30.00	100