| ⇢ | A | ContentTypes added |
| ⇢ | B | ContentTypes::buildContentTypesXML() added | |
| ⇢ | A | Relationships::buildWorkbookRelationshipsXML() added | |
| ⇢ | A | ContentTypes::setSheet() added | |
| ⇢ | A | Relationships::setSheet() added | |
| ⇢ | A | ContentTypes::__construct() added | |
| ⇢ | A | Relationships::__construct() added | |
| B | ↘ | C | ExcelWriter::writeToFile() got worse |
| B | ↛ | ExcelWriter::buildContentTypesXML() removed | |
| A | ↛ | ExcelWriter::buildWorkbookRelXML() removed |