Added calculation of Nash Sutcliffe efficiency coefficents. GET /api/data/nash-sutcliffe/{gauge}?when={WHEN} 'when' is optional in form of "2006-01-02T15:04:05.000" and defaults to current server time. curl -H "X-Gemma-Auth:$KEY" http://${server}:${port}/api/data/nash-sutcliffe/${gauge} | jq . { "when": "2019-03-20T10:38:05.687", "coeffs": [ { "value": 0, "samples": 0, "hours": 24 }, { "value": 0, "samples": 0, "hours": 48 }, { "value": 0, "samples": 0, "hours": 72 } ] }