Query: What has been the trend of my respiratory rate over the years?, FHIR Resource: {'resourceType': 'Observation', 'status': 'final', 'category': [{'coding': [{'system': 'http://terminology.hl7.org/CodeSystem/observation-category', 'code': 'vital-signs', 'display': 'Vital signs'}]}], 'code': {'coding': [{'system': 'http://loinc.org', 'code': '9279-1', 'display': 'Respiratory rate'}], 'text': 'Respiratory rate'}, 'subject': {'reference': 'urn:uuid:9d3c462d-67bf-e47d-6662-1972a3e58fd5'}, 'effectiveDateTime': '2017-02-07T06:56:09+05:30', 'valueQuantity': {'value': 16, 'unit': '/min', 'system': 'http://unitsofmeasure.org', 'code': '/min'}, 'interpretation': None}