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
0.08	1
0.11	2
0.13	3
0.15	4
0.17	5
0.19	6
0.21	7
0.23	8
0.25	9
0.27	10
0.30	11
0.34	12
0.34	13
0.38	14
0.40	15
0.43	16
0.47	17
0.51	18
0.53	19
0.57	20
0.61	21
0.64	22
0.68	23
0.71	24
0.76	25
0.78	26
0.83	27
0.86	28
0.88	29
0.94	30
1.01	31
1.02	32
1.03	33
1.08	34
1.13	35
1.17	36
1.17	37
1.23	38
1.26	39
1.29	40
1.34	41
1.40	42
1.41	43
1.45	44
1.51	45
1.55	46
1.60	47
1.65	48
1.68	49
1.74	50
1.75	51
1.77	52
1.81	53
1.88	54
1.95	55
2.01	56
2.03	57
2.09	58
2.15	59
2.22	60
2.26	61
2.34	62
2.34	63
2.36	64
2.46	65
2.52	66
2.60	67
2.67	68
2.72	69
2.80	70
2.87	71
3.01	72
3.02	73
3.04	74
3.17	75
3.26	76
3.37	77
3.50	78
3.52	79
3.63	80
3.76	81
3.88	82
4.02	83
4.14	84
4.25	85
4.40	86
4.58	87
4.68	88
4.88	89
5.04	90
5.29	91
5.52	92
5.80	93
6.13	94
6.51	95
7.02	96
7.52	97
8.35	98
9.77	99
25.40	100