From USADA 2018 report
Stimulants - 158 Approved
Anabolic Agents - 17 Approved
Glucocorticoids (steroids) - 57 Approved
Diuretics and Other Masking Agents - 33 Approved
Hormone and Metabolic Modulators - 26 Approved
Peptide Hormones, Growth Factors and Related Substances - 12 Approved
Narcotics - 13 Approved
Cannabinoids - 8 Approved
Beta-2 Agonists - 20 Approved
Again, that includes applications outside of the the registered testing pool, which is what is relevant for elite (Olympic, World, etc.) athletes. We are really talking about the Olympics here, aren't we? The statistics in the report say that, for applications for TUEs from the testing pool, 180 substances were considered and 86 were approved. It doesn't say how many athletes received exemptions but it would not be more than 86 and it could be less.