This might take a while to load.  Please be patient with it.  As viewed on the page, this chart is unclear.  Right click on it, select "Save Picture As...", and save it to your desktop.  Open the file.  Hold your mouse pointer over the chart.  In the lower right corner, a box should appear.  Click on that box.  It will expand the size of the chart, and make it easy to read.  There are 3 lines on the chart:  High weight, average weight, and low weight.  Week 4 is the only week without a value.  Feel free to e-mail me with more weight of female guinea pigs that are 52 weeks (1 year) or younger.