Talk:Architecture (Age of Empires II)/@comment-180.254.41.30-20170130152141/@comment-27274076-20170205113252

Okay let me try to break it down. Say a building has 1,000 HP. Masonry adds 10%, so 100 HP, resulting in a total of 1,100 HP. Now, if you research Architecture, the 10% are stacked, i.e. they are referring to the 1,100 HP the building has AFTER researching Masonry. And of 1,100 HP, 10% are 110 HP, which are 11% of the original 1,000 HP. If you now add it, you get +21% (of the original HP). I hope that was understandable.