set terminal png transparent xffffff

set size 0.6, 0.4

set output "access.png"
set xlabel "Year/Month"
set ylabel "PV"
set yrange [0:25000]
set xrange [0:29]
set xtics ("'04/5" 0, "'05/1" 8, "'06/1" 20, "'06/10" 29)
plot "access.txt" using 0:2 title "" with linespoints