Dear Statalist

I would like to make a graph bar but with percentages instead of the count. However, I am interested that those percentages to be 100% for each bar in total. In fact, I would like to mimic the percentage in the table below. Adding the option "percent" to the graph I´ll show below gives the percentages over the whole quantity, which is what I do not want to.
Is there any simple way to do it?

Thanks in advance.

Code:
tab x1 year, col
Code:
           |               year
        x1 |      2014       2017       2020 |     Total
-----------+---------------------------------+----------
         1 |     1,775      2,170      2,756 |     6,701 
           |     27.58      28.21      32.03 |     29.48 
-----------+---------------------------------+----------
         2 |     4,660      5,522      5,848 |    16,030 
           |     72.42      71.79      67.97 |     70.52 
-----------+---------------------------------+----------
     Total |     6,435      7,692      8,604 |    22,731 
           |    100.00     100.00     100.00 |    100.00
Code:
graph bar (count) x1, over(x2) over(year) asyvar stack blabel(bar, box bfcolor(white) pos(center) format(%4.2f) size(medium)) legend(off) ytitle("") title("from 2014")
Code:
* Example generated by -dataex-. To install: ssc install dataex
clear
input float(year x1 x2)
2014 1 1
2014 1 1
2014 2 2
2014 1 1
2014 2 2
2014 2 2
2014 1 1
2014 2 2
2014 2 2
2014 2 2
2014 . .
2014 . .
2014 . .
2014 2 2
2014 2 2
2014 2 2
2014 2 2
2014 2 2
2014 2 2
2014 2 2
2017 . .
2017 1 1
2017 2 2
2017 . .
2017 2 2
2017 2 2
2017 . .
2017 2 2
2017 1 1
2017 1 1
2017 2 2
2017 2 2
2017 2 2
2017 1 1
2017 2 2
2017 2 2
2017 2 2
2017 1 1
2017 1 1
2017 1 1
2017 2 2
2020 2 2
2020 1 1
2020 2 2
2020 1 1
2020 . .
2020 . .
2020 1 1
2020 1 1
2020 1 1
2020 2 2
2020 2 2
2020 2 2
2020 2 2
2020 2 2
2020 2 2
2020 2 2
2020 1 1
2020 2 2
2020 2 2
2020 2 2
2020 2 2
end