Hello everybody,

I would like to ask for help.

I would like to change the format of this data as below format, but I am confused about using code for doing that. Thank you in advance for your support.

```
df<-data.frame(
number = c(1L, 2L, 3L, 4L, 5L),
ticker = as.factor(c("AAA", "AAM", "AAT", "ABS", "ABT")),
X2008 = as.factor(c(" ", " ", " ", " ", " ")),
X2009 = as.factor(c(NA, "0.36%", NA, NA, "19.22%")),
X2010 = as.factor(c("3.99%", "1.44%", NA, NA, "15.60%")),
X2011 = as.factor(c("10.42%", "1.50%", NA, NA, "9.20%")),
X2012 = as.factor(c("21.61%", "2.65%", NA, NA, "7.21%")),
X2013 = as.factor(c("21.09%", "2.55%", NA, NA, "6.78%")),
X2014 = as.factor(c("20.59%", "0.97%", NA, NA, "7.47%")),
X2015 = as.factor(c("19.13%", "0.49%", NA, NA, "7.53%")),
X2016 = as.factor(c("17.49%", "0.57%", NA, NA, "4.14%")),
X2017 = as.factor(c("11.93%", "0.82%", NA, NA, "4.74%")),
X2018 = as.factor(c("9.88%", "0.98%", NA, NA, "2.77%"))
)
```