/Histo-y { 30 mul 100 add /y exch def 1993 sub 50 mul 150 add /x exch def 0.9 setgray newpath x 100 moveto x y lineto x 20 sub y lineto x 20 sub 100 lineto closepath fill 0 setgray newpath x 100 moveto x y lineto x 20 sub y lineto x 20 sub 100 lineto closepath stroke } def /Histo-z { 30 mul 100 add /y exch def 1993 sub 50 mul 150 add /x exch def 0.1 setgray newpath x 100 moveto x y lineto x 20 add y lineto x 20 add 100 lineto closepath fill 0 setgray newpath x 100 moveto x y lineto x 20 add y lineto x 20 add 100 lineto closepath stroke } def