How to generate bulk graphics using R
There are multiple ways you can achieve this. I guess the easiest would be to create a function that saves a bar chart for your KPI to a file:

save_KPI_plot &lt;- function(fn, kpi_data) {
    png(paste0(fn, ".png"))
    # Plot code
    dev.off()
}


You can call the function either as follows,

save_KPI_plot("kpi_1", kpi_1_data)


or store your file names in one list and your data in another and loop over both:

kpi_fns &lt;- list("filename_1", "filename_2")
kpi_data &lt;- list(kpi_1_data, kpi_2_data)
for (i in seq_along(kpi_fns)) {
    save_KPI_plot(kpi_fns[i], kpi_data[i])
}


If you prefer to have a different image format you can change png() to bmp() or jpeg().