Year	Ratio
1976-01-01	0.831480026245117
1989-01-01	0.910830020904541
1990-01-01	1.228379964828490
1991-01-01	1.232929944992070
1992-01-01	1.237360000610350
1993-01-01	1.172049999237060
1994-01-01	1.160130023956300
1995-01-01	1.169149994850160
1996-01-01	1.189620018005370
1998-01-01	1.317980051040650