# set terminal pngcairo  background "#ffffff" enhanced font "arial,10" fontscale 1.0 size 600, 400 
# set output 'histograms.1.png'
set key inside right top vertical Right noreverse noenhanced autotitle nobox
set datafile missing '-'
set style data linespoints
set xtics border in scale 1,0.5 nomirror rotate by -45  autojustify
set xtics  norangelimit
set xtics   ()
set title "US immigration from Europe by decade" 
x = 0.0
i = 22
plot 'immigration.dat' using 2:xtic(1) title columnheader(2), for [i=3:22] '' using i title columnheader(i)