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post/currency/v1/fluctuation2 credits

per-currency change over a date range: {CUR:{start_rate,end_rate,change,change_pct}} (derived from the range endpoints)

Working example
Parameters

Range start date (YYYY-MM-DD, inclusive). Only ECB working days inside the range are returned.

Range end date (YYYY-MM-DD, inclusive).

Base currency the rates are expressed in (ISO-4217). Defaults to EUR. Retired codes (RUB/HRK/legacy euro-joiners) work only for historical dates that predate their discontinuation.

Optional comma-separated target currencies to return (e.g. 'USD,GBP,JPY'). Omit to return every currency in the ECB set. Unknown codes are reported under 'unavailable', not rejected.

request preview
curl -X POST https://api.reefapi.com/currency/v1/fluctuation \
  -H "x-api-key: $REEF_KEY" \
  -H "content-type: application/json" \
  -d '{"start":"2024-01-02","end":"2024-01-31","base":"EUR","symbols":"USD"}'

Hit Send to run this endpoint live.