hi Matthew,
first thing you will need is the ability to have the proper date range in your report. from the screenshots you provided it looks like the data doesn't go back 3 months.
do you have a full version of the crystal reports designer or just a version embedded in PSA? if the latter, does PSA allow you to enter a date range starting 3 months ago?
if so, then when you create a new chart, make it a Line type, and the first On Change Of value should be your date field. you can then click on the date field in the On Change Of dialogue and choose Order and then set the time interval.
now add your shift field as the second On Change Of.
now add the hours worked field to the Show Value.
i hope this helps,
jamie