Hello.
thank you for your attention.
Is it possible for you to see my data and make a Proportional code for me?
I can not undrestand the xts function.
please help me if you can.
the data is uploaded in csv file below.
https://gofile.io/d/75nhuL
I run the code and get the error below:

library(tidyverse)
df <- df %>%
Error in .rowNamesDF<-(x, value = value) :
duplicate 'row.names' are not allowed
In addition: Warning message:
non-unique values when setting 'row.names': ‘1960’, ‘1961’, ‘1962’, ‘1963’, ‘1964’, ‘1965’, ‘1966’, ‘1967’, ‘1968’, ‘1969’, ‘1970’, ‘1971’, ‘1972’, ‘1973’, ‘1974’, ‘1975’, ‘1976’, ‘1977’, ‘1978’, ‘1979’, ‘1980’, ‘1981’, ‘1982’, ‘1983’, ‘1984’, ‘1985’, ‘1986’, ‘1987’, ‘1988’, ‘1989’, ‘1990’, ‘1991’, ‘1992’, ‘1993’, ‘1994’, ‘1995’, ‘1996’, ‘1997’, ‘1998’, ‘1999’, ‘2000’, ‘2001’, ‘2002’, ‘2003’, ‘2004’, ‘2005’, ‘2006’, ‘2007’, ‘2008’, ‘2009’, ‘2010’, ‘2011’, ‘2012’, ‘2013’, ‘2014’, ‘2015’, ‘2016’, ‘2017’, ‘2018’
myxts <- as.xts(df)
Error in as.POSIXlt.character(x, tz, ...) :
character string is not in a standard unambiguous format