Get SAR report in CSV

To get SAR report in CSV use sadf command.

To get memory report

sadf -d /var/log/sa/sa20 -- -r

In the above command sa20 is sar file of day 20. You can give any value between 1 to 31. 
-r gets you memory report.

Instead -r you can use following options:

To get report for CPU, Disk etc

# -d activity per block device
# -b IO and transfer rates
# -q load
# -u cpu
# -r memory utilization
# -R memory
# -B paging
# -S swap space utilization
# -W swap stats
# -n network
# -v kernel filesystem stats

# -w  context switches and task creation

CSV report will be needed if you wanted to visualize it in Excel or plotting in software such as Tableau, SAS, Python, PHP, JavaScript etc