2009

2010

2011

2012

2013

2014

2015

Predictive value

6.91

7.89

10.96

11.95

13.50

14.20

15.61

The true value

6.85

8.31

10.39

11.73

12.91

Error rate

0.86%

5.05%

5.49%

1.88%

4.57%