curl --request GET \
  --url https://macrobymark.com/api/indicators/{slug}/revisions \
  --header 'X-API-Key: <api-key>'

{
  "provider": "<string>",
  "seriesId": "<string>",
  "vintageDate": "<string>",
  "observations": "<array>",
  "fetchedAt": "2023-11-07T05:31:56Z"
}