I would keep it separate if you can. No two applicants probably do it exactly the same, and adcomms don't pore over these numbers super closely lookig for mistakes. You just want to give what you feel is a representative picture of your compensation. That's why I'd try to keep it separate if possible, rather than rolling it up into your base salary. Putting it in your base salary (if you don't have other options) isn't the end of other world; it's just not ideal.
For HBS I'd put it in "other compensation." They understand what that's usually used for.
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