Sum bucket aggregationedit
A sibling pipeline aggregation which calculates the sum across all buckets of a specified metric in a sibling aggregation. The specified metric must be numeric and the sibling aggregation must be a multibucket aggregation.
Syntaxedit
A sum_bucket
aggregation looks like this in isolation:
{ "sum_bucket": { "buckets_path": "the_sum" } }
Table 71. sum_bucket
Parameters
Parameter Name  Description  Required  Default Value 


The path to the buckets we wish to find the sum for (see 
Required 


The policy to apply when gaps are found in the data (see Dealing with gaps in the data for more details) 
Optional 


format to apply to the output value of this aggregation 
Optional 

The following snippet calculates the sum of all the total monthly sales
buckets:
POST /sales/_search { "size": 0, "aggs": { "sales_per_month": { "date_histogram": { "field": "date", "calendar_interval": "month" }, "aggs": { "sales": { "sum": { "field": "price" } } } }, "sum_monthly_sales": { "sum_bucket": { "buckets_path": "sales_per_month>sales" } } } }

And the following may be the response:
{ "took": 11, "timed_out": false, "_shards": ..., "hits": ..., "aggregations": { "sales_per_month": { "buckets": [ { "key_as_string": "2015/01/01 00:00:00", "key": 1420070400000, "doc_count": 3, "sales": { "value": 550.0 } }, { "key_as_string": "2015/02/01 00:00:00", "key": 1422748800000, "doc_count": 2, "sales": { "value": 60.0 } }, { "key_as_string": "2015/03/01 00:00:00", "key": 1425168000000, "doc_count": 2, "sales": { "value": 375.0 } } ] }, "sum_monthly_sales": { "value": 985.0 } } }