History of the Reserve of Depository Institutions - What does this even mean?

I was knocking around on the Federal Reserve Website [ http://www.federalreserve.gov/releases/h3/hist/] when I came across this information.  This is a partial depiction of the graph as the data goes back to 1959.  However, from 1959 to 2008 the lines are flat and liner, just as they appear here from 2003.  Obviously this sudden disturbance in these measures is related to the banking crisis, but I have no idea what this means.  I am posting it in hopes that someone familiar with the Fed and these data could provide some explanation.  Thank you in advance...