In order to bar graph x and y axis, it is typical for the (horizontal) x numbers to measure time or some designated number of units, and the (vertical) y numbers to measure how price, demand or some other variable will change as a result of the change in the x variable. The origin would be found where the x and y lines intersect (at coordinate {0,0}). A bar graph would be assembled by
. identifying and plotting a point {x,y} and then plotting it vertically from that point down to the x plane. Different points are then analyzed and compared in a bar graph. You can find more information here: http://nces.ed.gov/nceskids/graphing/classic/bar.asp
