curl --request POST \
  --url https://api.iotools.cloud/v1/tool/churn-rate-retention-calculator \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "period": "monthly",
  "customersStart": "1000",
  "customersLost": "50"
}
'

{
  "tool": "churn-rate-retention-calculator",
  "tool_version": "1.0.1",
  "outputs": {
    "result": [
      {
        "metric": "Monthly Churn Rate",
        "value": "5.00%"
      },
      {
        "metric": "Monthly Retention Rate",
        "value": "95.00%"
      },
      {
        "metric": "Annualized Churn Rate",
        "value": "45.96%"
      },
      {
        "metric": "Annualized Retention Rate",
        "value": "54.04%"
      },
      {
        "metric": "Customers at Start",
        "value": "1,000"
      },
      {
        "metric": "Customers Lost",
        "value": "50"
      },
      {
        "metric": "Customers Retained",
        "value": "950"
      }
    ]
  },
  "credits_used": 3,
  "credits_remaining": null
}