At the bottom there will be a small text box, this should have 24 or some number along this line, change that number to the amount of time you want the logs to be run to work out web and ftp status.
Make sure that you do not make the number to small otherwise the logs will not have enough time to finsh the logs and the end accounts will never gets there logs run. So make sure you use a number no less than 3-4 hours. A good number to use is about 6-12 hours, remember the small ther number the more the cpu has to spend in a day working out log files. Also depends on the amount of accounts you have and there log size.