In non-limiting examples of the present disclosure, systems, methods and devices for identifying a target value in a data set are presented. A request for a first target value in a data array may be received, wherein the request comprises first reference value. The data array may comprise a plurality of values and a plurality of value types included in one or more tables in a computer-implemented spreadsheet application. An index comprising a plurality of sorted reference numbers corresponding to a plurality of values in the data array may be generated based on the request. The index may be searched, and based at least on the search, the first reference value may be identified. In additional examples, the index may be cached and utilized to process additional target value requests that reference an overlapping range value with the first request.