I have a time series of annual returns.
I want to convert the percentages to an index.
For e.g. total return time series shows annual returns. I would like it to see it as
1998-12-31 100
1999-12-31. 111.6507
2000-12-31. 125.55
... ....
Many thanks
date total_return
1999-12-31 0.116507
2000-12-31 0.124500
2001-12-31 0.067565
2002-12-31 0.062774
2003-12-31 0.103384
2004-12-31 0.130776
2005-12-31 0.189867
2006-12-31 0.145452
2007-12-31 0.132526
2008-12-31 -0.079470
2009-12-31 -0.191446
2010-12-31 0.133377
2011-12-31 0.139314
2012-12-31 0.103205
2013-12-31 0.111638
2014-12-31 0.117227
2015-12-31 0.120510
2016-12-31 0.077795
2017-12-31 0.067697
2018-12-31 0.071384
2019-12-31 0.061313
