In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: This corresponds , by actuarial ( life table ) analysis , to a combined gall stone dissolution rate of 58 . 3 ( 15 . 9 % ) .
### Output Text:
This corresponds , by actuarial ( life table ) analysis , to a combined gall stone dissolution rate of 58 . 3 ( 15 . 9 % ) . 