curl --request GET \
  --url https://api.kit.com/v4/account/email_stats \
  --header 'X-Kit-Api-Key: <api-key>'

{
  "stats": {
    "sent": 6,
    "clicked": 3,
    "opened": 6,
    "email_stats_mode": "last_90",
    "open_tracking_enabled": true,
    "click_tracking_enabled": true,
    "starting": "2022-11-19T11:43:55Z",
    "ending": "2023-02-17T11:43:55Z",
    "open_rate": 100,
    "click_rate": 50,
    "unsubscribe_rate": 16.67,
    "bounce_rate": 16.67
  }
}