1 Relative frequency: the result of dividing the absolute frequency of a certain value by the total number of data.  The sum of the relative frequencies is equal to $$1$$. We can prove this easily by factorizing $$N$$. Cumulative frequency: the sum of absolute frequencies of all the values equal to or less than the considered value.
Having said that you should have to wait 8 years from the last FILING DATE of your previous bankruptcy. The old time period prior to 2005 was 7 years before you could file again, but that was expanded to 8 years after the Bankruptcy Abuse and Consumer Protection Act of 2005 was passed.
You can file for bankruptcy twice or even three times, even if you have received a discharge. The key is that you will often have to wait a certain period after you have filed and have received a discharge, to file for bankruptcy again and get a full discharge.