Stata程序如下:

use https://www.stata-press.com/data/r17/educ99gdp, clear
generate total = private + public
# delimit ;
graph bar (asis) public private ,
    over(country, sort(total) descending) stack //根据国别分组，根据总GDP进行降序排序，采取堆叠的形式
    title( "Spending on tertiary education as % of GDP, 1999",
    span pos(11) )
    subtitle(" ")  ylabel(-5(1)5)
    note("Source: OECD, Education at a Glance 2002", span)
;
# delimit cr


现在我想在图形上将堆积的总和，也就是total以点的形式标注在图形上，类似于如下的这个图形：

应该怎么添加标注呢？感谢各位大神！