Are you referring to USDA or FDA? FDA recently issued changes to nutrition and supplement panels.
Per FDA, the DV for added sugars for adults and children ages 4 years and older is 50 grams, based on a 2,000 calorie per day diet.
Therefore the calculation per serving size would be:
1. #grams added sugars per serving divided by 50 grams
2. multiply result by 100
Reference attached Federal Register / Vol. 81, No. 103 / Friday, May 27, 2016 / Rules and Regulations - page 33983
The updated daily value tables have not been posted to the CFR as of today, but you will be able to view the updated daily value information in 21 CFR 101.9 once it has been published.