Year Ratio 1985-01-01 0.351729989051819 1986-01-01 0.365779995918274 1987-01-01 0.398739993572235 1988-01-01 0.340050011873245 1989-01-01 0.324160009622574 1999-01-01 0.781610012054443 2003-01-01 0.686730027198792 2004-01-01 0.707409977912903 2005-01-01 0.707319974899292 2010-01-01 0.740000009536743 2011-01-01 0.691940009593964