Area plot style graph

I am trying to recreate a graph. There is 3 layers and i want the values of each layer to oscillate between particular values. I have the correct values stored in bl, gr and ye but when plotted onto the area graph they add to each other so end up oscillating around different values. I know this is because area plots sum up the values beneath it, but is there a way to recreate a similar looking graph but with the oscillation around the actual values i have calculated.

Also although i have 50 values i want the x axis on the graph to only go from 0-1, so any help with that is also appreciated.

This is what i have so far.

clc
clear all
close all

bl = 2.5 + (3.5-2.5).*rand(50,1);
gr = 1.5 + (2.5-1.5).*rand(50,1);
ye = 0.5 + (1.5-0.5).*rand(50,1);

y = [bl gr ye];

area(y)
colormap summer

Answer 1

[Thorsten]

 area([y(:, 1) diff(y')'])

Label the x-axis from 0 to 1:

 Nticks = 11; 
 xl = xlim; 
 set(gca, 'XTick', linspace(xl(1), xl(2), Nticks))
 set(gca, 'XTickLabel', linspace(0, 1, Nticks))

Answer 2

[Andy]

Thank you that was just what i was after, all working now.