Damage Reduction

Overview
Damage Reduction reduces incoming damage by set percentage, stacking multiplicatively with other effects. It modifies the damage after it has been reduced by the relevant Damage Resistance stat.
 * If a player has Dodgy 3 (-30%) and Lone Wanderer 3 (-20%) equipped, an incoming attack will be reduced by 44%.
 * DMGf = DMGi * 0.70 * 0.80

Fallout 76

 * Armor
 * Power armor passive (-7% per part, stacking additively)
 * Acrobat's armor (-50% per part, stacking additively)
 * Assassin's armor (-8% per part, stacking additively)
 * Cavalier sprinting armor (-15% per part, stacking additively)
 * Cavalier blocking armor (-15% per part, stacking additively)
 * Exterminator's armor (-15% per part, stacking additively)
 * Ghoul slayer's armor (-15% per part, stacking additively)
 * Hunter's armor (-15% per part, stacking additively)
 * Mutant slayer's armor (-15% per part, stacking additively)
 * Troubleshooter's armor (-15% per part, stacking additively)
 * Sentinel armor (-15% per part, stacking additively)
 * Zealot's armor (-15% per part, stacking additively)
 * Perks and mutations
 * Dodgy (-10/20/30%)
 * Fireproof (-15/30/45% fire and explosion only)
 * Lone Wanderer (-10/15/20%)
 * Blocker (-15/30/45% melee only)
 * Empath mutation (-25% for teammates, +33% for player)
 * Fallout 76 magazines
 * Astoundingly Awesome Tales #8
 * Live & Love #9
 * Scouts' Life #1
 * Scouts' Life #2
 * Scouts' Life #7
 * Tesla Science Magazine #1
 * Tesla Science Magazine #2
 * U.S. Covert Operations Manual #3
 * Aid
 * Cola perk bubblegum
 * Nuka-Cola Vaccinated/Scorched/My Blood's In It (-15%)