Re: Advice on boxes plot and setting xrange with a time axis

you forgot to 'set xdata time'

your plotfile should read:

...
set xdata time
set timefmt "%m.%Y"
set xrange ["12.1999":"01.2001"]
plot 'bars2.txt' using 1:2 title 'A'

or

...
set xdata time
set timefmt "%m.%Y"
set xrange ["12.1999":"01.2001"]
set timefmt "%m"
plot 'bars.txt' using 1:2 title 'A'

you may adjust the xrange more precisely:

...
set timefmt "%d.%m.%Y"
set xrange ["15.12.1999":"18.12.2000"]
set timefmt "%m.%Y"
plot 'bars2.txt' using 1:2 title 'A'