clipBy is optional and should only be set when groupBy (above) is set. clipBy allows you to control the behavior in the case where groupBy and the requested date range do not line up exactly. Possible values are: "OUTER", "INNER". For example, you request interval data and specify groupBy=MONTH with a date range of April 15, 2012 through June 15, 2012, OUTER will include all months that overlap at least part of the requested range, and the response will include the months of April, May and June. INNER will only include the full months within the requested range, so only May is returned. When you pass in a groupBy but do not specify clipBy, INNER is used. (Optional)