This data is so granular for covering nearly a decade. I can probably dig up all of my former offer letters with initial salaries and approximate (read: entirel

This data is so granular for covering nearly a decade. I can probably dig up all of my former offer letters with initial salaries and approximate (read: entirely inaccurate) equity values, but I doubt I can dig up records on every cash or stock bonus I've received. If someone wanted to construct a page like this for themselves, where would they get the data to do it? Maybe something related to tax records? Or do you just need to have had the foresight to record/save all of this from the get-go?